Combination therapy of HSP90 inhibitors with BRAF inhibitors

ABSTRACT

A pharmaceutical combination comprising a BRAF inhibitor, and an Hsp90 inhibitor according to the following formulae (I): or a tautomer, or a pharmaceutically acceptable salt thereof, wherein the variables are defined therein. Also provided is a method for treating a proliferative disorder in a subject in need thereof, using the pharmaceutical combination described herein.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application is a 35 U.S.C. §371 national stage filing of International Application No. PCT/US2012/064967, filed on Nov. 14,2012, which claims the benefit of U.S. Provisional Patent Application No. 61/559,486, filed on Nov. 14, 2011. The contents of each of the above applications are incorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION

Although tremendous advances have been made in elucidating the genomic abnormalities that cause malignant cancer cells, currently available chemotherapy remains unsatisfactory, and the prognosis for the majority of patients diagnosed with cancer remains dismal. Most chemotherapeutic agents act on a specific molecular target thought to be involved in the development of the malignant phenotype. However, a complex network of signaling pathways regulate cell proliferation and the majority of malignant cancers are facilitated by multiple genetic abnormalities in these pathways. Therefore, it is less likely that a therapeutic agent that acts on one molecular target will be fully effective in curing a patient who has cancer.

Heat shock proteins (HSPs) are a class of chaperone proteins that are up-regulated in response to elevated temperature and other environmental stresses, such as ultraviolet light, nutrient deprivation and oxygen deprivation. HSPs act as chaperones to other cellular proteins (called client proteins), facilitate their proper folding and repair and aid in the refolding of misfolded client proteins. There are several known families of HSPs, each having its own set of client proteins. The Hsp90 family is one of the most abundant HSP families accounting for about 1-2% of proteins in a cell that is not under stress and increasing to about 4-6% in a cell under stress. Inhibition of Hsp90 results in the degradation of its client proteins via the ubiquitin proteasome pathway. Unlike other chaperone proteins, the client proteins of Hsp90 are mostly protein kinases or transcription factors involved in signal transduction, and a number of its client proteins have been shown to be involved in the progression of cancer.

SUMMARY OF THE INVENTION

It is now found that certain triazolone Hsp90 inhibitor and BRAF inhibitor combinations are surprisingly effective at treating subjects with certain cancers without further increasing the side effect profile of the single agents. The particular combination therapies disclosed herein demonstrate surprising and significant anticancer effects.

In an embodiment, the present invention provides a method of utilizing Hsp90 inhibitors according to formulae (I) or (Ia), or a compound in Tables 1 or 2 for the treatment of proliferative disorders, such as cancer, in combination with a BRAF inhibitor. In an embodiment, the method includes treating a subject with cancer comprising the step of administering to the subject an Hsp90 inhibitor according to formulae (I) or (Ia), or a compound in Tables 1 or 2 and a BRAF inhibitor. In an embodiment, the administration of the Hsp90 inhibitor and the BRAF inhibitor are done concurrently. In another embodiment, the administration of the Hsp90 inhibitor and the BRAF inhibitor are done sequentially. In another embodiment, the administration of the Hsp90 inhibitor and the BRAF inhibitor are dosed independently. In any one of these embodiments, the BRAF inhibitor may be PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®). In any one of these embodiments, the Hsp90 inhibitor may be a compound represented in Tables 1 or 2. In any one of these embodiments, the BRAF inhibitor may be PLX-4032.

In some embodiments, the cancer may have mutations or translocations in the EGFR, K-Ras, c-Met, HER2, B-Raf, PI3K and/or ALK proteins. In some embodiments, the cancer may express wild-type EGFR and K-Ras. In some embodiments, the cancer may express mutated EGFR and wild type K-Ras. In some embodiments, the cancer may express wild-type EGFR and mutated K-Ras protein. In some embodiments, the cancer may be ALK positive (“ALK+”.) In some embodiments, the cancer may have the EML4-ALK translocation. In some embodiments, the cancer may have the HER2 mutation. In some embodiments, the cancer may have a mutation in PI3K. In some embodiments, the cancer may have a B-Raf protein mutation.

In some embodiments, the present invention also provides kits for administration of the combination therapy. In an embodiment, the kit includes separate pharmaceutical compositions containing the Hsp90 inhibitor according to formulae (I) or (Ia) or a compound in Tables 1 or 2, and a BRAF inhibitor. In another embodiment, the kit includes one pharmaceutical composition containing both the Hsp90 inhibitor and the BRAF inhibitor. In any of these embodiments, each pharmaceutical composition includes one or more pharmaceutically acceptable carrier or diluent. In any one of these embodiments, the BRAF inhibitor may be PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®). In one of these embodiments, the Hsp90 inhibitor may be a compound represented in Tables 1 or 2. In any one of these embodiments, the BRAF inhibitor may be PLX-4032.

In an embodiment, the invention includes use of an Hsp90 inhibitor according to formulae (I) or (Ia) or a compound in Tables 1 or 2 for the manufacture of a medicament for treating cancer in combination with a BRAF inhibitor.

In an embodiment, the method includes the treatment of drug-resistant cancer in a subject by administering an effective amount of the pharmaceutical combination comprising an Hsp90 compound according to formulae (I) or (Ia) or a compound in Tables 1 or 2 and a BRAF inhibitor. In an embodiment, the method further comprises the administration of one or more therapeutic agents in addition to the pharmaceutical combination of an Hsp90 compound according to formulae (I) or (Ia) or a compound in Tables 1 or 2 and a BRAF inhibitor. In certain embodiments, the combination treatment utilizing an Hsp90 compound according to formulae (I) or (Ia) or a compound in Tables 1 or 2 with a BRAF inhibitor to help to arrest, partially or fully, or reduce the development of drug resistant cancer in a subject. In this embodiment, the combinations described herein may allow a reduced dose of the BRAF inhibitor given to a subject, because the Hsp90 inhibitor should inhibit the development of multidrug resistant cancerous cells. In an embodiment, the BRAF inhibitor may be PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®). In another embodiment, the BRAF inhibitor may be PLX-4032.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of some embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.

FIG. 1 shows western blot analysis of indicated analytes in A375 cells treated with ganetespib (referred to as “Compound I”) or BEZ235 for 24 hr at indicated concentrations.

FIG. 2 shows western blot analysis of indicated analytes in A375 cells treated with ganetespib for 24 hr at indicated concentrations.

FIG. 3 shows western blot analysis of indicated analytes in A375 cells treated with ganetespib, PLX-4032 or AZD6244 for 24 hr at indicated concentrations.

FIG. 4 shows cytotoxicity assessment in A375 cells treated with ganetespib, PLX-4032 or their combinations for 72 hr.

FIG. 5 shows western blot analysis of indicated analytes in RPMI-7951 cells treated with ganetespib, AZD6244, or PLX-4032 for 24 hr at indicated concentrations.

FIG. 6 shows significant in vivo treatment result by the combination of ganetespib with PLX4032 after A375 xenograft implantation.

DETAILED DESCRIPTION OF THE INVENTION

Definitions

Unless otherwise specified, the below terms used herein are defined as follows:

As used herein, the term “alkyl” means a saturated or unsaturated, straight chain or branched, non-cyclic hydrocarbon having from 1 to 10 carbon atoms. Representative straight chain alkyls include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl and n-decyl; while representative branched alkyls include isopropyl, sec-butyl, isobutyl, tert-butyl, isopentyl, 2-methylbutyl, 3-methylbutyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, 2,3-dimethylbutyl, 2,3-dimethylpentyl, 2,4-dimethylpentyl, 2,3-dimethylhexyl, 2,4-dimethylhexyl, 2,5-dimethylhexyl, 2,2-dimethylpentyl, 2,2-dimethylhexyl, 3,3-dimtheylpentyl, 3,3-dimethylhexyl, 4,4-dimethylhexyl, 2-ethylpentyl, 3-ethylpentyl, 2-ethylhexyl, 3-ethylhexyl, 4-ethylhexyl, 2-methyl-2-ethylpentyl, 2-methyl-3-ethylpentyl, 2-methyl-4-ethylpentyl, 2-methyl-2-ethylhexyl, 2-methyl-3-ethylhexyl, 2-methyl-4-ethylhexyl, 2,2-diethylpentyl, 3,3-diethylhexyl, 2,2-diethylhexyl, 3,3-diethylhexyl, and the like. The term “(C₁-C₆)alkyl” means a saturated, straight chain or branched, non-cyclic hydrocarbon having from 1 to 6 carbon atoms. Alkyl groups included in compounds described herein may be optionally substituted with one or more substituents. Examples of unsaturated alkyls include vinyl, allyl, 1-butenyl, 2-butenyl, isobutylenyl, 1-pentenyl, 2-pentenyl, 3-methyl-1-butenyl, 2-methyl-2-butenyl, 2,3-dimethyl-2-butenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 1-heptenyl, 2-heptenyl, 3-heptenyl, 1-octenyl, 2-octenyl, 3-octenyl, 1-nonenyl, 2-nonenyl, 3-nonenyl, 1-decenyl, 2-decenyl, 3-decenyl, acetylenyl, propynyl, 1-butynyl, 2-butynyl, 1-pentynyl, 2-pentynyl, 3-methyl-1-butynyl, 4-pentynyl, 1-hexynyl, 2-hexynyl, 5-hexynyl, 1-heptynyl, 2-heptynyl, 6-heptynyl, 1-octynyl, 2-octynyl, 7-octynyl, 1-nonynyl, 2-nonynyl, 8-nonynyl, 1-decynyl, 2-decynyl, 9-decynyl, and the like. Alkyl groups included in compounds described herein may be optionally substituted with one or more substituents.

As used herein, the term “cycloalkyl” means a saturated or unsaturated, mono- or polycyclic, non-aromatic hydrocarbon having from 3 to 20 carbon atoms. Representative cycloalkyls include cyclopropyl, 1-methylcyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, octahydropentalenyl, cyclohexenyl, cyclooctenyl, cyclohexynyl, and the like. Cycloalkyl groups included in compounds described herein may be optionally substituted with one or more substituents.

As used herein, the term “alkylene” refers to an alkyl group that has two points of attachment. The term “(C₁-C₆)alkylene” refers to an alkylene group that has from one to six carbon atoms. Straight chain (C₁-C₆)alkylene groups are preferred. Non-limiting examples of alkylene groups include methylene (—CH₂—), ethylene (—CH₂CH₂—), n-propylene (—CH₂CH₂CH₂—), isopropylene (—CH₂CH(CH₃)—), and the like. Alkylene groups may be saturated or unsaturated, and may be optionally substituted with one or more substituents.

As used herein, the term “lower” refers to a group having up to four atoms. For example, a “lower alkyl” refers to an alkyl radical having from 1 to 4 carbon atoms, “lower alkoxy” refers to “—O—(C₁-C₄)alkyl.

As used herein, the term “haloalkyl” means an alkyl group, in which one or more, including all, the hydrogen radicals are replaced by a halo group(s), wherein each halo group is independently selected from —F, —Cl, —Br, and —I. For example, the term “halomethyl” means a methyl in which one to three hydrogen radical(s) have been replaced by a halo group. Representative haloalkyl groups include trifluoromethyl, bromomethyl, 1,2-dichloroethyl, 4-iodobutyl, 2-fluoropentyl, and the like.

As used herein, an “alkoxy” is an alkyl group which is attached to another moiety via an oxygen linker. Alkoxy groups included in compounds described herein may be optionally substituted with one or more substituents.

As used herein, a “haloalkoxy” is a haloalkyl group which is attached to another moiety via an oxygen linker.

As used herein, the term an “aromatic ring” or “aryl” means a mono- or polycyclic hydrocarbon, containing from 6 to 15 carbon atoms, in which at least one ring is aromatic. Examples of suitable aryl groups include phenyl, tolyl, anthracenyl, fluorenyl, indenyl, azulenyl, and naphthyl, as well as benzo-fused carbocyclic moieties such as 5,6,7,8-tetrahydronaphthyl. Aryl groups included in compounds described herein may be optionally substituted with one or more substituents. In one embodiment, the aryl group is a monocyclic ring, wherein the ring comprises 6 carbon atoms, referred to herein as “(C₆)aryl.”

As used herein, the term “aralkyl” means an aryl group that is attached to another group by a (C₁-C₆)alkylene group. Representative aralkyl groups include benzyl, 2-phenyl-ethyl, naphth-3-yl-methyl and the like. Aralkyl groups included in compounds described herein may be optionally substituted with one or more substituents.

As used herein, the term “heterocyclyl” means a monocyclic or a polycyclic, saturated or unsaturated, non-aromatic ring or ring system which typically contains 5- to 20-members and at least one heteroatom. A heterocyclic ring system can contain saturated ring(s) or unsaturated non-aromatic ring(s), or a mixture thereof. A 3- to 10-membered heterocycle can contain up to 5 heteroatoms, and a 7- to 20-membered heterocycle can contain up to 7 heteroatoms. Typically, a heterocycle has at least one carbon atom ring member. Each heteroatom is independently selected from nitrogen, which can be oxidized (e.g., N(O)) or quaternized, oxygen and sulfur, including sulfoxide and sulfone. The heterocycle may be attached via any heteroatom or carbon atom. Representative heterocycles include morpholinyl, thiomorpholinyl, pyrrolidinonyl, pyrrolidinyl, piperidinyl, piperazinyl, hydantoinyl, valerolactamyl, oxiranyl, oxetanyl, tetrahydrofuranyl, tetrahydropyranyl, tetrahydropyrindinyl, tetrahydropyrimidinyl, tetrahydrothiophenyl, tetrahydrothiopyranyl, and the like. A heteroatom may be substituted with a protecting group known to those of ordinary skill in the art, for example, a nitrogen atom may be substituted with a tert-butoxycarbonyl group. Furthermore, the heterocyclyl included in compounds described herein may be optionally substituted with one or more substituents. Only stable isomers of such substituted heterocyclic groups are contemplated in this definition.

As used herein, the term “heteroaryl”, or like terms, means a monocyclic or a polycyclic, unsaturated radical containing at least one heteroatom, in which at least one ring is aromatic. Polycyclic heteroaryl rings must contain at least one heteroatom, but not all rings of a polycyclic heteroaryl moiety must contain heteroatoms. Each heteroatom is independently selected from nitrogen, which can be oxidized (e.g., N(O)) or quaternized, oxygen and sulfur, including sulfoxide and sulfone. Representative heteroaryl groups include pyridyl, 1-oxo-pyridyl, furanyl, benzo[1,3]dioxolyl, benzo[1,4]dioxinyl, thienyl, pyrrolyl, oxazolyl, imidazolyl, thiazolyl, an isoxazolyl, quinolinyl, pyrazolyl, isothiazolyl, pyridazinyl, pyrimidinyl, pyrazinyl, a triazinyl, triazolyl, thiadiazolyl, isoquinolinyl, indazolyl, benzoxazolyl, benzofuryl, indolizinyl, imidazopyridyl, tetrazolyl, benzimidazolyl, benzothiazolyl, benzothiadiazolyl, benzoxadiazolyl, indolyl, tetrahydroindolyl, azaindolyl, imidazopyridyl, quinazolinyl, purinyl, pyrrolo[2,3]pyrimidinyl, pyrazolo[3,4]pyrimidinyl, imidazo[1,2-a]pyridyl, and benzothienyl. In an embodiment, the heteroaromatic ring is selected from 5-8 membered monocyclic heteroaryl rings. The point of attachment of a heteroaromatic or heteroaryl ring may be at either a carbon atom or a heteroatom. Heteroaryl groups included in compounds described herein may be optionally substituted with one or more substituents. As used herein, the term “(C₅)heteroaryl” means an heteroaromatic ring of 5 members, wherein at least one carbon atom of the ring is replaced with a heteroatom, such as, for example, oxygen, sulfur or nitrogen. Representative (C₅)heteroaryls include furanyl, thienyl, pyrrolyl, oxazolyl, imidazolyl, thiazolyl, isoxazolyl, pyrazolyl, isothiazolyl, pyrazinyl, triazolyl, thiadiazolyl, and the like. As used herein, the term “(C₆)heteroaryl” means an aromatic heterocyclic ring of 6 members, wherein at least one carbon atom of the ring is replaced with a heteroatom such as, for example, oxygen, nitrogen or sulfur. Representative (C₆)heteroaryls include pyridyl, pyridazinyl, pyrazinyl, triazinyl, tetrazinyl, and the like.

As used herein, the term “heteroaralkyl” means a heteroaryl group that is attached to another group by a (C₁-C₆)alkylene. Representative heteroaralkyls include 2-(pyridin-4-yl)-propyl, 2-(thien-3-yl)-ethyl, imidazol-4-yl-methyl, and the like. Heteroaralkyl groups included in compounds described herein may be optionally substituted with one or more substituents.

As used herein, the term “halogen” or “halo” means —F, —Cl, —Br or —I.

Suitable substituents for an alkyl, alkylene, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, heterocyclyl, aryl, aralkyl, heteroaryl, and heteroaralkyl groups include are those substituents which form a stable compound described herein without significantly adversely affecting the reactivity or biological activity of the compound described herein. Examples of substituents for an alkyl, alkylene, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, heterocyclyl, aryl, aralkyl, heteroaryl, and heteroaralkyl include an alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, heterocyclyl, aryl, heteroaryl, aralkyl, heteraralkyl, heteroalkyl, alkoxy, (each of which can be optionally and independently substituted), —C(O)NR²⁸R²⁹, —C(S)NR²⁸R²⁹, —C(NR³²)NR²⁸R²⁹, —NR³³C(O)R³¹, —NR³³C(S)R³¹, —NR³³C(NR³²)R³¹, halo, —OR³³, cyano, nitro, —C(O)R³³, —C(S)R³³, —C(NR³²)R³³, —NR²⁸R²⁹, —C(O)OR³³, —C(S)OR³³, —C(NR³²)OR³³, —OC(O)R³³, —OC(S)R³³, —OC(NR³²)R³³, —NR³⁰C(O)NR²⁸R²⁹, —NR³³C(S)NR²⁸R²⁹, —NR³³C(NR³²)NR²⁸R²⁹, —OC(O)NR²⁸R²⁹, —OC(S)NR²⁸R²⁹, —OC(NR³²)NR²⁸R²⁹, —NR³³C(O)OR³¹, —NR³³C(S)OR³¹, —NR³³C(NR³²)OR³¹, —S(O)_(k)R³³, —OS(O)_(k)R³³, —NR³³S(O)_(k)R³³, —S(O)_(k)NR²⁸R²⁹, —OS(O)_(k)NR²⁸R²⁹, —NR³³S(O)_(k)NR²⁸R²⁹, guanidino, —C(O)SR³¹, —C(S)SR³¹, —C(NR³²)SR³¹, —OC(O)OR³¹, —OC(S)OR³¹, —OC(NR³²)OR³¹, —SC(O)R³³, —SC(O)OR³¹, —SC(NR³²)OR³¹, —SC(S)R³³, —SC(S)OR³¹, —SC(O)NR²⁸R²⁹, —SC(NR³²)NR²⁸R²⁹, —SC(S)NR²⁸R²⁹, —SC(NR³²)R³³, —OS(O)_(k)OR³¹, —S(O)_(k)OR³¹, —NR³⁰S(O)_(k)OR³¹, —SS(O)_(k)R³³, —SS(O)_(k)OR³¹, —SS(O)_(k)NR²⁸R²⁹, —OP(O)(OR³¹)₂, or —SP(O)(OR³¹)₂. In addition, any saturated portion of an alkyl, cycloalkyl, alkylene, heterocyclyl, alkenyl, cycloalkenyl, alkynyl, aralkyl and heteroaralkyl groups, may also be substituted with ═O, ═S, or ═N—R³². Each R²⁸ and R²⁹ is independently H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, heterocyclyl, aryl, heteroaryl, aralkyl, or heteraralkyl, wherein each alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, heterocyclyl, aryl, heteroaryl, aralkyl, or heteroalkyl represented by R²⁸ or R²⁹ is optionally and independently substituted. Each R³⁰, R³¹ and R³³ is independently H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, heterocyclyl, aryl, heteroaryl, aralkyl, or heteraralkyl, wherein each alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, heterocyclyl, aryl, heteroaryl, aralkyl, and heteraralkyl represented by R³⁰ or R³¹ or R³³ is optionally and independently unsubstituted. Each R³² is independently H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, heterocyclyl, aryl, heteroaryl, aralkyl, heteraralkyl, —C(O)R³³, —C(O)NR²⁸R²⁹, —S(O)_(k)R³³, or —S(O)_(k)NR²⁸R²⁹, wherein each alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, heterocyclyl, aryl, heteroaryl, aralkyl and heteraralkyl represented by R³² is optionally and independently substituted. The variable k is 0, 1 or 2. In some embodiments, suitable substituents include C1-C4 alkyl, C1-C4 haloalkyl, C1-C4 alkoxy, C1-C4 haloalkoxy, C1-C4 hydroxyalkyl, halo, or hydroxyl.

When a heterocyclyl, heteroaryl or heteroaralkyl group contains a nitrogen atom, it may be substituted or unsubstituted. When a nitrogen atom in the aromatic ring of a heteroaryl group has a substituent, the nitrogen may be oxidized or a quaternary nitrogen.

Unless indicated otherwise, the compounds described herein containing reactive functional groups, such as, for example, carboxy, hydroxy, thiol and amino moieties, also include corresponding protected derivatives thereof. “Protected derivatives” are those compounds in which a reactive site or sites are blocked with one ore more protecting groups. Examples of suitable protecting groups for hydroxyl groups include benzyl, methoxymethyl, allyl, trimethylsilyl, tert-butyldimethylsilyl, acetate, and the like. Examples of suitable amine protecting groups include benzyloxycarbonyl, tert-butoxycarbonyl, tert-butyl, benzyl and fluorenylmethyloxy-carbonyl (Fmoc). Examples of suitable thiol protecting groups include benzyl, tert-butyl, acetyl, methoxymethyl and the like. Other suitable protecting groups are well known to those of ordinary skill in the art and include those found in T. W. GREENE, PROTECTING GROUPS IN ORGANIC SYNTHESIS, (John Wiley & Sons, Inc., 1981).

As used herein, the term “compound(s) described herein” or similar terms refers to a compound of formulae (I), or (Ia) or a compound in Tables 1 or 2 or a tautomer or pharmaceutically acceptable salt thereof. Also included in the scope of the embodiments are a solvate, clathrate, hydrate, polymorph, prodrug, or protected derivative of a compound of formulae (I), or (Ia), or a compound in Tables 1 or 2.

The compounds described herein may contain one or more chiral centers and/or double bonds and, therefore, exist as stereoisomers, such as double-bond isomers (i.e., geometric isomers), enantiomers or diastereomers. Each chemical structure shown herein, including the compounds described herein, encompass all of the corresponding compound' enantiomers, diastereomers and geometric isomers, that is, both the stereochemically pure form (e.g., geometrically pure, enantiomerically pure, or diastereomerically pure) and isomeric mixtures (e.g., enantiomeric, diastereomeric and geometric isomeric mixtures). In some cases, one enantiomer, diastereomer or geometric isomer will possess superior activity or an improved toxicity or kinetic profile compared to other isomers. In those cases, such enantiomers, diastereomers and geometric isomers of compounds described herein are preferred.

When a disclosed compound is named or depicted by structure, it is to be understood that solvates (e.g., hydrates) of the compound or a pharmaceutically acceptable salt thereof is also included. “Solvates” refer to crystalline forms wherein solvent molecules are incorporated into the crystal lattice during crystallization. Solvates may include water or nonaqueous solvents such as ethanol, isopropanol, DMSO, acetic acid, ethanolamine and ethyl acetate. When water is the solvent molecule incorporated into the crystal lattice of a solvate, it is typically referred to as a “hydrate”. Hydrates include stoichiometric hydrates as well as compositions containing variable amounts of water.

When a disclosed compound is named or depicted by structure, it is to be understood that the compound, including solvates thereof, may exist in crystalline forms, non-crystalline forms or a mixture thereof. The compounds or solvates may also exhibit polymorphism (i.e., the capacity to occur in different crystalline forms). These different crystalline forms are typically known as “polymorphs.” It is to be understood that when named or depicted by structure, the disclosed compounds and solvates (e.g., hydrates) also include all polymorphs thereof. Polymorphs have the same chemical composition but differ in packing, geometrical arrangement and other descriptive properties of the crystalline solid state. Polymorphs, therefore, may have different physical properties such as shape, density, hardness, deformability, stability and dissolution properties. Polymorphs typically exhibit different melting points, IR spectra and X-ray powder diffraction patterns, which may be used for identification. One of ordinary skill in the art will appreciate that different polymorphs may be produced, for example, by changing or adjusting the conditions used in crystallizing the compound. For example, changes in temperature, pressure or solvent may result in different polymorphs. In addition, one polymorph may spontaneously convert to another polymorph under certain conditions.

When a disclosed compound is named or depicted by structure, it is to be understood that clathrates (“inclusion compounds”) of the compound or its pharmaceutically acceptable salt, solvate or polymorph, are also included. “Clathrate” means a compound described herein, or a salt thereof, in the form of a crystal lattice that contains spaces (e.g., channels) that have a guest molecule trapped within (e.g., a solvent or water).

As used herein, and unless otherwise indicated, the term “prodrug” means a derivative of a compound that can hydrolyze, oxidize, or otherwise react under biological conditions (in vitro or in vivo) to provide a compound described herein. Prodrugs may become active upon such reaction under biological conditions, or they may have activity in their unreacted forms. Examples of prodrugs contemplated herein include analogs or derivatives of compounds of formulae (I) or (Ia) or a compound in Tables 1 or 2 that comprise biohydrolyzable moieties such as biohydrolyzable amides, biohydrolyzable esters, biohydrolyzable carbamates, biohydrolyzable carbonates, biohydrolyzable ureides and phosphate analogues. Prodrugs can typically be prepared using well-known methods, such as those described by BURGER'S MEDICINAL CHEMISTRY AND DRUG DISCOVERY, (Manfred E. Wolff Ed., 5^(th) ed. (1995)) 172-178, 949-982.

The articles “a”, “an” and “the” are used herein to refer to one or to more than one (i.e. to at least one) of the grammatical object of the article unless otherwise clearly indicated by contrast. By way of example, “an element” means one element or more than one element.

The term “including” is used herein to mean, and is used interchangeably with, the phrase “including but not limited to”.

The term “or” is used herein to mean, and is used interchangeably with, the term “and/or,” unless context clearly indicates otherwise.

The term “such as” is used herein to mean, and is used interchangeably, with the phrase “such as but not limited to”.

Unless specifically stated or obvious from context, as used herein, the term “about” is understood as within a range of normal tolerance in the art, for example within 2 standard deviations of the mean. About can be understood as within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated value. Unless otherwise clear from context, all numerical values provided herein can be modified by the term about.

As used herein, the terms “subject”, “patient” and “mammal” are used interchangeably. The terms “subject” and “patient” refer to an animal (e.g., a bird such as a chicken, quail or turkey, or a mammal), preferably a mammal including a non-primate (e.g., a cow, pig, horse, sheep, rabbit, guinea pig, rat, cat, dog, and mouse) and a primate (e.g., a monkey, chimpanzee and a human), and more preferably a human. In an embodiment, the subject is a non-human animal such as a farm animal (e.g., a horse, cow, pig or sheep), or a pet (e.g., a dog, cat, guinea pig or rabbit). In another embodiment, the subject is a human.

As used herein, “Hsp90” includes each member of the family of heat shock proteins having a mass of about 90-kiloDaltons. For example, in humans the highly conserved Hsp90 family includes the cytosolic Hsp90α and Hsp90β isoforms, as well as GRP94, which is found in the endoplasmic reticulum, and HSP75/TRAP1, which is found in the mitochondrial matrix.

The Raf family of proto-oncogenes (A-raf, B-raf and C-raf) was first identified when C-raf was discovered due to its homology with v-raf, the transforming gene of the mouse sarcoma virus 3611. A-raf was later discovered by screening a cDNA library under low stringency conditions using a v-raf probe, and B-raf was discovered due to its homology with C-Rmil, a transforming gene in avian retrovirus Mill Hill No. 2. The Raf family of proteins is involved in the Ras/Raf/MEK/ERK pathway, referred to herein as the “MAP kinase pathway” (MEK stands for “MAPK/ERK kinase” and ERK stands for “extracellularly regulated kinases”), which has been implicated in the genesis and progression of many human cancers through upregulation of cell division and proliferation. All raf proteins are serine/threonine kinases which are capable of activating the MAP kinase pathway. However, B-raf is far more potent at activating this pathway than A-raf or C-raf, and mutations in the gene encoding B-raf are more common in cancer. For example, B-raf mutations have been identified in 60% to 70% of malignant melanomas, 83% of anaplastic thyroid carcinoma, 35% to 69% of papillary thyroid carcinoma, 4% to 16% of colon cancer, 63% of low-grade ovarian carcinoma, 15% of Barrett's esophageal carcinoma, 4% of acute myeloid leukemia, 3-4.8% of head and neck squamous cell carcinoma, 2%-3% of non-small-cell lung cancer, 2% of gastric carcinoma, 2% of non-Hodgkin's lymphoma and has been reported in glioma, sarcoma, breast cancer, cholangiocarcinoma, and liver cancer. Most mutations in B-raf that have been found in human cancers are point mutations that occur in the kinase domain and are clustered in exons 11 and 15 of the gene which contains several regulatory phosphorylation sites (S446, S447, D448, D449, T599, and S602). (Beeram, et al., Journal of Clinical Oncology (2005), 23(27):6771-6790). The most prevalent mutation is the T1799A transversion mutation which accounts for more than 80% of mutations in the BRAF gene and results in a V600E mutation in B-raf. The V600E was formerly designated V599E (the gene mutation was designated T1796A) due to a mistake in the GenBank nucleotide sequence NM 004333. The corrected GenBank sequence is NT 007914 and designates the protein mutation as V600E and the gene mutation as T1799A. This corrected numbering will be used herein. This mutation is thought to mimic phosphorylation in the activation segment of B-raf since it inserts a negatively charged residue near two activating phosphorylation sites, T599 and S602, and thus results in constitutively active B-raf in a Ras independent manner. (Xing, M., Endocrine-Related Cancer (2005), 12:245-262).

Treatment of cancer cells with 17AAG has been shown to stimulate the degradation of B-raf, and mutant forms of B-raf have been shown to be more sensitive to degradation than the wild type. For example, when melanoma cell line A375 which contain the V600E mutation was treated with 17AAG, B-raf was degraded more rapidly than in CHL cells which contained wild type B-raf. Other B-raf mutants (e.g., V600D, G469A, G469E, G596R, G466V, and G594V) were a found to be degraded more rapidly than wild type B-raf when transvected into COS cells. However, B-raf mutants E586K and L597V were not sensitive to degradation when cells were treated with 17AAG. Therefore, it is believed that wild type B-raf in its activated form is a client protein of Hsp90 and that most mutated forms of B-raf are more dependent on Hsp90 for folding, stability and/or function than the wild type protein. (Dias, et al., Cancer Res. (2005), 65(23): 10686-10691). The B-raf inhibitors as used herein include PLX-4032 (vemurafenib, CAS No.: 918504-65-1), GDC-0879 (CAS No.: 905281-76-7), PLX-4720 (CAS No.: 918505-84-7), and sorafenib (Nexavar®) (CAS No.: 475207-59-1).

The term “c-Kit” or “c-Kit kinase” refers to a membrane receptor protein tyrosine kinase which is preferably activated upon binding Stem Cell Factor (SCF) to its extracellular domain. Yarden, et al., Embo. J., (1987) 11:3341-3351; Qiu, et al., Embo. J., (1988) 7:1003-1011. The full length amino acid sequence of a c-Kit kinase preferably is as set forth in Yarden, et al.; and Qiu, et al., which are incorporated by reference herein in their entirety, including any drawings. Mutant versions of c-Kit kinase are encompassed by the term “c-Kit” or “c-Kit kinase” and include those that fall into two classes: (1) having a single amino acid substitution at codon 816 of the human c-Kit kinase, or its equivalent position in other species (Ma, et al., J. Invest Dermatol., (1999) 112:165-170), and (2) those which have mutations involving the putative juxtamembrane z-helix of the protein (Ma, et al., J. Biol. Chem., (1999) 274:13399-13402). Both of these publications are incorporated by reference herein in their entirety, including any drawings.

As used herein, “BCR-ABL” is a fusion protein that results from the translocation of gene sequences from c-ABL protein tyrosine kinase on chromosome 9 into BCR sequences on chromosome 22 producing the Philadelphia chromosome. A schematic representation of human BCR, ABL and BCR-ABL can be seen in FIG. 1 of U.S. patent application Ser. No. 10/193,651, filed on Jul. 9, 2002. Depending on the breaking point in the BCR gene, BCR-ABL fusion proteins can vary in size from 185-230 kDa but they must contain at least the OLI domain from BCR and the TK domain from ABL for transforming activity. The most common BCR-ABL gene products found in humans are P230 BCR-ABL, P210 BCR-ABL and P190 BCR-ABL. P210 BCR-ABL is characteristic of CML and P190 BCR-ABL is characteristic of ALL.

FLT3 kinase is a tyrosine kinase receptor involved in the regulation and stimulation of cellular proliferation. Gilliland, et al., Blood (2002), 100:1532-42. The FLT3 kinase has five immunoglobulin-like domains in its extracellular region, as well as an insert region of 75-100 amino acids in the middle of its cytoplasmic domain. FLT3 kinase is activated upon the binding of the FLT3 ligand which causes receptor dimerization. Dimerization of the FLT3 kinase by FLT3 ligand activates the intracellular kinase activity as well as a cascade of downstream substrates including Stat5, Ras, phosphatidylinositol-3-kinase (PI3K), Erk2, Akt, MAPK, SHC, SHP2 and SHIP. Rosnet, et al., Acta Haematol. (1996), 95:218; Hayakawa, et al., Oncogene (2000), 19:624; Mizuki, et al., Blood (2000), 96:3907; Gilliand, et al., Curr. Opin. Hematol. (2002), 9: 274-81. Both membrane-bound and soluble FLT3 ligand bind, dimerize, and subsequently activate the FLT3 kinase.

Normal cells that express FLT3 kinase include immature hematopoietic cells, typically CD34+ cells, placenta, gonads and brain. Rosnet, et al., Blood (1993), 82:1110-19; Small, et al., Proc. Natl. Acad. Sci. U.S.A. (1994), 91:459-63; Rosnet, et al., Leukemia (1996), 10:238-48. However, efficient stimulation of proliferation via FLT3 kinase typically requires other hematopoietic growth factors or interleukins. FLT3 kinase also plays a critical role in immune function through its regulation of dendritic cell proliferation and differentiation. McKenna, et al., Blood (2000), 95:3489-497. Numerous hematologic malignancies express FLT3 kinase, the most prominent of which is AML. Yokota, et al., Leukemia (1997), 11:1605-09. Other FLT3 expressing malignancies include B-precursor cell acute lymphoblastic leukemias, myelodysplastic leukemias, T-cell acute lymphoblastic leukemias, and chronic myelogenous leukemias. Rasko, et al., Leukemia (1995), 9:2058-66.

FLT3 kinase mutations associated with hematologic malignancies are activating mutations. In other words, the FLT3 kinase is constitutively activated without the need for binding and dimerization by FLT3 ligand, and therefore stimulates the cell to grow continuously. Two types of activating mutations have been identified: internal tandem duplications (ITDs) and point mutation in the activating loop of the kinase domain. As used herein, the term “FLT3 kinase” refers to both wild type FLT3 kinase and mutant FLT3 kinases, such as FLT3 kinases that have activating mutations. Compounds provided herein are useful in treating conditions characterized by inappropriate FLT3 activity, such as proliferative disorders. Inappropriate FLT3 activity includes, but is not limited to, enhanced FLT3 activity resulting from increased or de novo expression of FLT3 in cells, increased FLT3 expression or activity and FLT3 mutations resulting in constitutive activation. The existence of inappropriate or abnormal FLT3 ligand and FLT3 levels or activity can be determined using well known methods in the art. For example, abnormally high FLT3 levels can be determined using commercially available ELISA kits. FLT3 levels can also be determined using flow cytometric analysis, immunohistochemical analysis and in situ hybridization techniques.

“Epidermal growth factor receptor” or “EGFR”, as used herein, means any epidermal growth factor receptor (EGFR) protein, peptide, or polypeptide having EGFR or EGFR family activity (e.g., Her1, Her2, Her3 and/or Her4), such as encoded by EGFR Genbank Accession Nos. shown in Table I of U.S. patent application Ser. No. 10/923,354, filed on Aug. 20, 2004, or any other EGFR transcript derived from a EGFR gene and/or generated by EGFR translocation. The term “EGFR” is also meant to include other EGFR protein, peptide, or polypeptide derived from EGFR isoforms (e.g., Her1, Her2, Her3 and/or Her4), mutant EGFR genes, splice variants of EGFR genes, and EGFR gene polymorphisms.

EGFR is a member of the type 1 subgroup of receptor tyrosine kinase family of growth factor receptors which play critical roles in cellular growth, differentiation and survival. Activation of these receptors typically occurs via specific ligand binding which results in hetero- or homodimerization between receptor family members, with subsequent autophosphorylation of the tyrosine kinase domain. Specific ligands which bind to EGFR include epidermal growth factor (EGF), transforming growth factor α (TGFα), amphiregulin and some viral growth factors. Activation of EGFR triggers a cascade of intracellular signaling pathways involved in both cellular proliferation (the ras/raf/MAP kinase pathway) and survival (the PI3 kinase/Akt pathway). Members of this family, including EGFR and HER2, have been directly implicated in cellular transformation.

A number of human malignancies are associated with aberrant or overexpression of EGFR and/or overexpression of its specific ligands. Gullick, Br. Med. Bull. (1991), 47:87-98; Modijtahedi & Dean, Int. J. Oncol. (1994), 4:277-96; Salomon, et al., Crit. Rev. Oncol. Hematol. (1995), 19:183-232. Aberrant or overexpression of EGFR has been associated with an adverse prognosis in a number of human cancers, including head and neck, breast, colon, prostate, lung (e.g., NSCLC, adenocarcinoma and squamous lung cancer), ovarian, gastrointestinal cancers (gastric, colon, pancreatic), renal cell cancer, bladder cancer, glioma, gynecological carcinomas and prostate cancer. In some instances, overexpression of tumor EGFR has been correlated with both chemoresistance and a poor prognosis. Lei, et al., Anti-cancer Res. (1999), 19:221-28; Veale, et al., Br. J. Cancer (1993); 68:162-65. Mutations in EGFR are associated with many types of cancer as well. For example, EGFR mutations are highly prevalent in non-mucinous BAC patients. Finberg, et al., J. Mol. Diagnostics (2007) 9(3):320-26.

c-Met is a receptor tyrosine kinase that is encoded by the Met protooncogene and transduces the biological effects of hepatocyte growth factor (HGF), which is also referred to as scatter factor (SF). Jiang et al., Crit. Rev. Oncol. Hematol. 29: 209-248 (1999), the entire teachings of which are incorporated herein by reference. c-Met and HGF are expressed in numerous tissues, although their expression is normally confined predominantly to cells of epithelial and mesenchymal origin, respectively. c-Met and HGF are required for normal mammalian development and have been shown to be important in cell migration, cell proliferation and survival, morphogenic differentiation, and organization of 3-dimensional tubular structures (e.g., renal tubular cells, gland formation, etc.). The c-Met receptor has been shown to be expressed in a number of human cancers. c-Met and its ligand, HGF, have also been shown to be co-expressed at elevated levels in a variety of human cancers (particularly sarcomas). However, because the receptor and ligand are usually expressed by different cell types, c-Met signaling is most commonly regulated by tumor-stroma (tumor-host) interactions. Furthermore, c-Met gene amplification, mutation, and rearrangement have been observed in a subset of human cancers. Families with germine mutations that activate c-Met kinase are prone to multiple kidney tumors as well as tumors in other tissues. Numerous studies have correlated the expression of c-Met and/or HGF/SF with the state of disease progression of different types of cancer (including lung, colon, breast, prostate, liver, pancreas, brain, kidney, ovaries, stomach, skin, and bone cancers). Furthermore, the overexpression of c-Met or HGF have been shown to correlate with poor prognosis and disease outcome in a number of major human cancers including lung, liver, gastric, and breast.

The anaplastic lymphoma kinase (ALK) tyrosine kinase receptor is an enzyme that in humans is encoded by the ALK gene. The 2;5 chromosomal translocation is frequently associated with anaplastic large cell lymphomas (ALCLs). The translocation creates a fusion gene consisting of the ALK (anaplastic lymphoma kinase) gene and the nucleophosmin (NPM) gene: the 3′ half of ALK, derived from chromosome 2, is fused to the 5′ portion of NPM from chromosome 5. The product of the NPM-ALK fusion gene is oncogenic. Other possible translocations of the ALK gene, such as the eml4 translocation, are also implicated in cancer.

The general role of ALK in cancer has been described. See e.g. Pulford et al., J. Cell Physiol. 199(3): 330-358 (2004). Abnormalities in the anaplastic lymphoma kinase (ALK) gene have an established pathogenic role in many pediatric and adult cancers, including non-small cell lung cancer (NSCLC), diffuse large B-cell lymphoma (DLBCL), anaplastic large cell lymphoma (ALCL), neuroblastoma (NBL), and inflammatory myofibroblastic tumors (IMT), non-Hodgkin's lymphoma (NHL), and esophageal squamous cell carcinoma (ESCC). These diseases account for more than 250,000 new cancer diagnoses each year in the United States alone.

More particularly, EML4-ALK and KIF5B-ALK translocations have been found in non-small cell lung cancer. See. e.g. Mano H., Cancer Sci. 2008 December; 99(12):2349-55; Takeuchi K et al., Clin Cancer Res. 2009 May 1; 15(9):3143-9. CLTC-ALK mutation has been found in DLBCL. See e.g. Rudzki Z et al., Pol J Pathol. 2005; 56 (1):37-45. NPM-ALK, MSN-ALK, and other mutations have been found in ALCL. See e.g. Lamant L et al., Genes Chromosomes Cancer. 2003 August; 37 (4):427-32; Webb T R et al. Expert Rev Anticancer Ther 2009 March; 9(3):331-56. TPM4-ALK mutation has been found in esophageal squamous cell carcinoma (ESCC). See e.g. Li R, Morris S W., Med Res Rev. 2008 May; 28 (3):372-412. F1174L, R1275Q, and other point mutations have been found in NBL. See e.g. van Roy N et al. Genome Med 2009 July 27; 1 (7):74. TPM3-ALK, TPM4-ALK, CLTC-ALK, RanBP2-ALK, and TPM4-ALK mutations have been found in IMT. See e.g. Gleason B C, Hornick J L. J Clin Pathol 2008 April; 61(4):428-37. The methods of detection and identification of these alterations, mutations or rearrangements in an ALK gene or gene product can be found in those above-identified references and references cited therein.

The KRAS oncogene (the cellular homolog of the Kirsten rat sarcoma virus gene) is a critical gene in the development of a variety of cancers, and the mutation status of this gene is an important characteristic of many cancers. Mutation status of the gene can provide diagnostic, prognostic and predictive information for several cancers. The KRAS gene is a member of a family of genes (KRAS, NRAS and HRAS). KRAS is a member of the RAS family of oncogenes, a collection of small guanosine triphosphate (GTP)-binding proteins that integrate extracellular cues and activate intracellular signaling pathways to regulate cell proliferation, differentiation, and survival. Gain-of-function mutations that confer transforming capacity are frequently observed in KRAS, predominantly arising as single amino acid substitutions at amino acid residues G12, G13 or Q61. Constitutive activation of KRAS leads to the persistent stimulation of downstream signaling pathways that promote tumorigenesis, including the RAF/MEK/ERK and PI3K/AKT/mTOR cascades. In NSCLC, KRAS mutations are highly prevalent (20-30%) and are associated with unfavorable clinical outcomes. Mutations in KRAS appear mutually exclusive with those in EGFR in NSCLC tumors; more importantly, they can account for primary resistance to targeted EGFR TKI therapies. Mutations in the KRAS gene are common in many types of cancer, including pancreatic cancer (˜65%), colon cancer (˜40%), lung cancer (˜20%) and ovarian cancer (˜15%).

The methods and procedures for the detections and/or identifications of EGFR, KRAS, BRAF and/or ALK over-expressions and/or mutations are known in the literature and can be easily carried out by a skilled person. See, e.g., U.S. Pat. Nos. 7,700,339; 5,529,925; 5,770,421; U.S. Patent Application Publication No. US2011/0110923; Palmer et al, Biochem. J. (2009), 345-361; Koivunen et al, Clin. Can. Res., 2008, 14, 4275-4283; Anderson, Expert Rev. Mol. Diagn. 11(6), 635-642 (2011); Pinto et al, Cancer Genetics 204 (2011), 439-446; Rekhtman et al; Clin Cancer Res 2012; 18:1167-1176; Massarelli et al, Clin Cancer Res 2007; 13:2890-2896; Lamy et al, Modern Pathology (2011) 24, 1090-1100; Balschun et al, Expert Rev. Mol. Diagn. 11(8), 799-802 (2011); Vakiani et al, J Pathol 2011; 223, 219-229; Okudela et al, Pathology International 2010; 60: 651-660; John et al, Oncogene (2009) 28, S14-S23; Jimeno et al, J. Clin. Oncol. 27, 1130-1135 (2009); Van Krieken et al, Virchows Archiv. 453, 417-431 (2008); and the references cited in the-above identified references. Thresholds of increased expression that constitute an EGFR mutation or an ALK mutation are well known in the art. Moreover, it is generally recognized that once an EGFR mutation is detected in a cancer, the KRAS mutation will be eliminated in the same cancer. Put reversely, if a KRAS mutation is positively identified in a cancer from a subject, it is then not necessary to engage in any further EGFR related identification. Similar principle can be applied to an ALK mutation in a cancer. That is if there is an ALK mutation detected in a cancer, it is extremely rare that an EGFR or KRAS mutation will be implicated. Stated another way, once an ALK mutation is positively identified in a cancer, no further identification is necessary either for EGFR mutation or for KRAS mutation in the same cancer.

As used herein, a “proliferative disorder” or a “hyperproliferative disorder,” and other equivalent terms, means a disease or medical condition involving pathological growth of cells. Proliferative disorders include cancer, smooth muscle cell proliferation, systemic sclerosis, cirrhosis of the liver, adult respiratory distress syndrome, idiopathic cardiomyopathy, lupus erythematosus, retinopathy, (e.g., diabetic retinopathy or other retinopathies), cardiac hyperplasia, reproductive system associated disorders such as benign prostatic hyperplasia and ovarian cysts, pulmonary fibrosis, endometriosis, fibromatosis, harmatomas, lymphangiomatosis, sarcoidosis and desmoid tumors. Non-cancerous proliferative disorders also include hyperproliferation of cells in the skin such as psoriasis and its varied clinical forms, Reiter's syndrome, pityriasis rubra pilaris, hyperproliferative variants of disorders of keratinization (e.g., actinic keratosis, senile keratosis), scleroderma, and the like. In one embodiment, the proliferative disorder is cancer.

In an embodiment, the invention provides a method of treating a proliferative disorder in a subject, comprising administering to the subject an effective amount of the combination of an Hsp90 inhibitor and a BRAF inhibitor as described herein. In an embodiment, the proliferative disorder is cancer. In an embodiment, the cancer may be breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, testicular tumor, ovarian cancer, lymphoma, leukemia, multiple myeloma, or colon cancer. In an embodiment, the cancer may be solid cancer, gastric cancer, bladder cancer, ovarian cancer, melanoma, or colorectal cancer. In an embodiment, the cancer may be colon cancer. In an embodiment, the cancer may be metastatic colorectal cancer. In an embodiment, the cancer may be bladder cancer. In an embodiment, the cancer may be solid cancer. In an embodiment, the cancer may be gastric cancer. In another embodiment, the cancer may be melanoma. In another embodiment, the melanoma may have a BRAF mutation. In an embodiment, the cancer may have a mutation or translocation in EGFR, K-ras, PI3K, ALK, HER2neu and/or B-raf proteins. Some of the disclosed methods can be particularly effective at treating subjects whose cancer has become “drug resistant” or “multi-drug resistant”. A cancer which initially responded to an anti-cancer drug becomes resistant to the anti-cancer drug when the anti-cancer drug is no longer effective in treating the subject with the cancer. For example, many tumors will initially respond to treatment with an anti-cancer drug by decreasing in size or even going into remission, only to develop resistance to the drug. “Drug resistant” tumors are characterized by a resumption of their growth and/or reappearance after having seemingly gone into remission, despite the administration of increased dosages of the anti-cancer drug. Cancers that have developed resistance to two or more anti-cancer drugs are said to be “multi-drug resistant”. For example, it is common for cancers to become resistant to three or more anti-cancer agents, often five or more anti-cancer agents and at times ten or more anti-cancer agents.

Other anti-proliferative or anti-cancer therapies may be combined with the pharmaceutical combination of this invention to treat proliferative diseases and cancer. Other therapies or anti-cancer agents that may be used in combination with the inventive anti-cancer agents of the present invention include surgery, radiotherapy (including, but not limited to, gamma-radiation, neutron beam radiotherapy, electron beam radiotherapy, proton therapy, brachytherapy, and systemic radioactive isotopes), endocrine therapy, biologic response modifiers (including, but not limited to, interferons, interleukins, and tumor necrosis factor (TNF)), hyperthermia and cryotherapy, agents to attenuate any adverse effects (e.g., antiemetics), and other approved chemotherapeutic drugs. In an embodiment, the pharmaceutical combination described herein may be administered with one or more therapeutic agents selected from DFMO, vandetanib, trastuzumab, temodar, dexamethasone, epirubicin, ifosfamide, mitoxantrone, vorinostat, interferon alpha, rituximab, prednisone, cyclophosphamide, bendamustine, adriamycin, valproate, celecoxib, thalidomide, nelarabine, methotrexate, filgrastim, gemtuzumab ozogamicin, testosterone, clofarabine, cytarabine, everolimus, rituxumab, busulfan, capecitabine, pegfilgrastim, mesna, amrubicin, obatoclax, gefitinib, cyclosporine, dasatinib, temozolomide, thiotepa, plerixafor, mitotane, vincristine, doxorubicin, cixutumumab, endostar, fenofibrate, melphalan, sunitinib, rubitecan, enoxaparin, isotretinoin, tariquidar, pomalidomide, altretamine, idarubicin, rapamycin, zevalin, everolimus, pravastatin, carmustine, nelfinavir, streptozocin, tirapazamine, aprepitant, lenalidomide, G-CSF, procarbazine, alemtuzumab, amifostine, valspodar, lomustine, oblimersen, temsirolimus, vinblastine, figitumumab, belinostat, niacinamide, tipifarnib, estramustine, erlotinib, bevacizumab, paclitaxel, docetaxel, Abraxane®, pemetrexed, bortezomib, cetuximab, gemcitabine, 5-fluorouracil, leucovorin and tetracycline. In an embodiment, the one or more therapeutic agent is selected from erlotinib, bevacizumab, bortezomib, paclitaxel, doxorubicin, docetaxel, mitoxantrone, cytarabine, 5-fluorouracil, leucovorin, pemetrexed and vincristine.

As used herein, the term “pharmaceutically acceptable salt” refers to a salt prepared from a compound of formulae (I) or (Ia) or a compound in Tables 1 or 2 having an acidic functional group, such as a carboxylic acid functional group, and a pharmaceutically acceptable inorganic or organic base. Suitable bases include hydroxides of alkali metals such as sodium, potassium, and lithium; hydroxides of alkaline earth metal such as calcium and magnesium; hydroxides of other metals, such as aluminum and zinc; ammonia, and organic amines, such as unsubstituted or hydroxy-substituted mono-, di-, or trialkylamines; dicyclohexylamine; tributyl amine; pyridine; N-methyl, N-ethylamine; diethylamine; triethylamine; mono-, bis-, or tris-(2-hydroxy-lower alkyl amines), such as mono-, bis-, or tris-(2-hydroxyethyl)amine, 2-hydroxy-tert-butylamine, or tris-(hydroxymethyl)methylamine, N,N,-di-lower alkyl-N-(hydroxy lower alkyl)-amines, such as N,N-dimethyl-N-(2-hydroxyethyl)amine, or tri-(2-hydroxyethyl)amine; N-methyl-D-glucamine; and amino acids such as arginine, lysine, and the like. The term “pharmaceutically acceptable salt” also refers to a salt prepared from a compound of formulae (I) or (Ia) or a compound in Tables 1 or 2 having a basic functional group, such as an amine functional group, and a pharmaceutically acceptable inorganic or organic acid. Suitable acids include hydrogen sulfate, citric acid, acetic acid, oxalic acid, hydrochloric acid (HCl), hydrogen bromide (HBr), hydrogen iodide (HI), nitric acid, hydrogen bisulfide, phosphoric acid, isonicotinic acid, oleic acid, tannic acid, pantothenic acid, saccharic acid, lactic acid, salicylic acid, tartaric acid, bitartratic acid, ascorbic acid, succinic acid, maleic acid, besylic acid, fumaric acid, gluconic acid, glucaronic acid, formic acid, benzoic acid, glutamic acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, pamoic acid and p-toluenesulfonic acid.

As used herein, the term “pharmaceutically acceptable solvate,” is a solvate formed from the association of one or more pharmaceutically acceptable solvent molecules to one of the compounds of formulae (I) or (Ia) or a compound in Tables 1 or 2. The term “solvate” includes hydrates, e.g., hemihydrate, monohydrate, dihydrate, trihydrate, tetrahydrate, and the like.

A pharmaceutically acceptable carrier may contain inert ingredients which do not unduly inhibit the biological activity of the compound(s) described herein. The pharmaceutically acceptable carriers should be biocompatible, i.e., non-toxic, non-inflammatory, non-immunogenic and devoid of other undesired reactions upon the administration to a subject. Standard pharmaceutical formulation techniques can be employed, such as those described in REMINGTON, J. P., REMINGTON'S PHARMACEUTICAL SCIENCES (Mack Pub. Co., 17th ed., 1985). Suitable pharmaceutical carriers for parenteral administration include, for example, sterile water, physiological saline, bacteriostatic saline (saline containing about 0.9% mg/ml benzyl alcohol), phosphate-buffered saline, Hank's solution, Ringer's-lactate, and the like. Methods for encapsulating compositions, such as in a coating of hard gelatin or cyclodextran, are known in the art. See BAKER, ET AL., CONTROLLED RELEASE OF BIOLOGICAL ACTIVE AGENTS, (John Wiley and Sons, 1986).

As used herein, the term “effective amount” refers to an amount of a compound described herein which is sufficient to reduce or ameliorate the severity, duration, progression, or onset of a disease or disorder, delay onset of a disease or disorder, retard or halt the advancement of a disease or disorder, cause the regression of a disease or disorder, prevent or delay the recurrence, development, onset or progression of a symptom associated with a disease or disorder, or enhance or improve the therapeutic effect(s) of another therapy. In an embodiment of the invention, the disease or disorder is a proliferative disorder. The precise amount of compound administered to a subject will depend on the mode of administration, the type and severity of the disease or condition and on the characteristics of the subject, such as general health, age, sex, body weight and tolerance to drugs. For example, for a proliferative disease or disorder, determination of an effective amount will also depend on the degree, severity and type of cell proliferation. The skilled artisan will be able to determine appropriate dosages depending on these and other factors. When co-administered with other therapeutic agents, e.g., when co-administered with an anti-cancer agent, an “effective amount” of any additional therapeutic agent(s) will depend on the type of drug used. Suitable dosages are known for approved therapeutic agents and can be adjusted by the skilled artisan according to the condition of the subject, the type of condition(s) being treated and the amount of a compound of the invention being used. In cases where no amount is expressly noted, an effective amount should be assumed. Non-limiting examples of an effective amount of a compound described herein are provided herein below. In a specific embodiment, the invention provides a method of treating, managing, or ameliorating a disease or disorder, e.g. a proliferative disorder, or one or more symptoms thereof, the method comprising administering to a subject in need thereof a dose of the Hsp90 inhibitor at least 150 μg/kg, at least 250 μg/kg, at least 500 μg/kg, at least 1 mg/kg, at least 5 mg/kg, at least 10 mg/kg, at least 25 mg/kg, at least 50 mg/kg, at least 75 mg/kg, at least 100 mg/kg, at least 125 mg/kg, at least 150 mg/kg, or at least 200 mg/kg or more of one or more compounds described herein once every day, once every 2 days, once every 3 days, once every 4 days, once every 5 days, once every 6 days, once every 7 days, once every 8 days, once every 10 days, once every two weeks, once every three weeks, or once a month.

The dosage of the individual BRAF inhibitors used in the pharmaceutical combination may be equal to or lower than the dose of an individual therapeutic agent when given independently to treat, manage, or ameliorate a disease or disorder, or one or more symptoms thereof. In an embodiment of the invention, the disease or disorder being treated with a combination therapy is a proliferative disorder. In an embodiment, the proliferative disorder is cancer. In an embodiment, the BRAF inhibitor PLX-4032 is administered at a dose of between about 200 mg to about 2000 mg. In an embodiment, PLX-4032 is administered at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg twice daily. In an embodiment, PLX-4032 is administered at a dose of about 480 mg twice daily. In an embodiment, PLX-4032 is administered at about 720 mg twice daily. In an embodiment, PLX-4032 is administered at about 960 mg twice daily. The recommended dosages of therapeutic agents currently used for the treatment, management, or amelioration of a disease or disorder, or one or more symptoms thereof, can obtained from any reference in the art. For a more in depth review of dosage and treatment schedules for various disorders, see, e.g., GOODMAN & GILMAN'S THE PHARMACOLOGICAL BASIS OF BASIS OF THERAPEUTICS 9^(TH) ED, (Hardman, et al., Eds., NY:Mc-Graw-Hill (1996)); PHYSICIAN'S DESK REFERENCE 57^(TH) ED. (Medical Economics Co., Inc., Montvale, N.J. (2003)).

As used herein, the terms “treat”, “treatment” and “treating” refer to the reduction or amelioration of the progression, severity and/or duration of a disease or disorder, delay of the onset of a disease or disorder, or the amelioration of one or more symptoms (preferably, one or more discernible symptoms) of a disease or disorder, resulting from the administration of one or more therapies (e.g., one or more therapeutic agents such as a compound of the invention). The terms “treat”, “treatment” and “treating” also encompass the reduction of the risk of developing a disease or disorder, and the delay or inhibition of the recurrence of a disease or disorder. In an embodiment, the disease or disorder being treated is a proliferative disorder such as cancer. In specific embodiments, the terms “treat”, “treatment” and “treating” refer to the amelioration of at least one measurable physical parameter of a disease or disorder, such as growth of a tumor, not necessarily discernible by the patient. In other embodiments the terms “treat”, “treatment” and “treating” refer to the inhibition of the progression of a disease or disorder, e.g., a proliferative disorder, either physically by the stabilization of a discernible symptom, physiologically by the stabilization of a physical parameter, or both. In another embodiment, the terms “treat”, “treatment” and “treating” of a proliferative disease or disorder refers to the reduction or stabilization of tumor size or cancerous cell count, and/or delay of tumor formation. In another embodiment, the terms “treat”, “treating” and “treatment” also encompass the administration of a compound described herein as a prophylactic measure to patients with a predisposition (genetic or environmental) to any disease or disorder described herein.

As used herein, the terms “therapeutic agent” and “therapeutic agents” refer to any agent(s) that can be used in the treatment of a disease or disorder, e.g. a proliferative disorder, or one or more symptoms thereof. In certain embodiments, the term “therapeutic agent” refers to a compound described herein. In certain other embodiments, the term “therapeutic agent” does not refer to a compound described herein. Preferably, a therapeutic agent is an agent that is known to be useful for, or has been or is currently being used for the treatment of a disease or disorder, e.g., a proliferative disorder, or one or more symptoms thereof.

As used herein, the term “synergistic” refers to a combination of a compound described herein and another therapeutic agent, which, when taken together, is more effective than the additive effects of the individual therapies. A synergistic effect of a combination of therapies (e.g., a combination of therapeutic agents) permits the use of lower dosages of one or more of the therapeutic agent(s) and/or less frequent administration of the agent(s) to a subject with a disease or disorder, e.g., a proliferative disorder. The ability to utilize lower the dosage of one or more therapeutic agent and/or to administer the therapeutic agent less frequently reduces the toxicity associated with the administration of the agent to a subject without reducing the efficacy of the therapy in the treatment of a disease or disorder. In addition, a synergistic effect can result in improved efficacy of agents in the prevention, management or treatment of a disease or disorder, e.g. a proliferative disorder. Finally, a synergistic effect of a combination of therapies may avoid or reduce adverse or unwanted side effects associated with the use of either therapeutic agent alone.

As used herein, the phrase “side effects” encompasses unwanted and adverse effects of a therapeutic agent. Side effects are always unwanted, but unwanted effects are not necessarily adverse. An adverse effect from a therapeutic agent might be harmful or uncomfortable or risky to a subject. Side effects include fever, chills, lethargy, gastrointestinal toxicities (including gastric and intestinal ulcerations and erosions), nausea, vomiting, neurotoxicities, nephrotoxicities, renal toxicities (including such conditions as papillary necrosis and chronic interstitial nephritis), hepatic toxicities (including elevated serum liver enzyme levels), myelotoxicities (including leukopenia, myelosuppression, thrombocytopenia and anemia), dry mouth, metallic taste, prolongation of gestation, weakness, somnolence, pain (including muscle pain, bone pain and headache), hair loss, asthenia, dizziness, extra-pyramidal symptoms, akathisia, cardiovascular disturbances and sexual dysfunction.

As used herein, the term “in combination” refers to the use of more than one therapeutic agent. The use of the term “in combination” does not restrict the order in which the therapeutic agents are administered to a subject with a disease or disorder, e.g., a proliferative disorder. A first therapeutic agent, such as a compound described herein, can be administered prior to (e.g., 5 minutes, 15 minutes, 30 minutes, 45 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 12 hours, 24 hours, 48 hours, 72 hours, 96 hours, 1 week, 2 weeks, 3 weeks, 4 weeks, 5 weeks, 6 weeks, 8 weeks, or 12 weeks before), concomitantly with, or subsequent to (e.g., 5 minutes, 15 minutes, 30 minutes, 45 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 12 hours, 24 hours, 48 hours, 72 hours, 96 hours, 1 week, 2 weeks, 3 weeks, 4 weeks, 5 weeks, 6 weeks, 8 weeks, or 12 weeks after) the administration of a second therapeutic agent, such as an anti-cancer agent, to a subject with a disease or disorder, e.g. a proliferative disorder, such as cancer. In an embodiment, the Hsp90 inhibitor and the BRAF inhibitor are dosed on independent schedules. In another embodiment, the Hsp90 inhibitor and the BRAF inhibitor are dosed on approximately the same schedule. In another embodiment, the Hsp90 inhibitor and the BRAF inhibitor are dosed concurrently or sequentially on the same day.

As used herein, the terms “therapies” and “therapy” can refer to any protocol(s), method(s), and/or agent(s) that can be used in the prevention, treatment, management, or amelioration of a disease or disorder, e.g., a proliferative disorder, or one or more symptoms thereof.

A used herein, a “protocol” includes dosing schedules and dosing regimens. The protocols herein are methods of use and include therapeutic protocols.

As used herein, a composition that “substantially” comprises a compound means that the composition contains more than about 80% by weight, more preferably more than about 90% by weight, even more preferably more than about 95% by weight, and most preferably more than about 97% by weight of the compound.

As used herein, a “racemic mixture” means about 50% of one enantiomer and about 50% of is corresponding enantiomer of the molecule. The combination encompasses all enantiomerically-pure, enantiomerically-enriched, diastereomerically pure, diastereomerically enriched, and racemic mixtures of the compounds described herein. Enantiomeric and diastereomeric mixtures can be resolved into their component enantiomers or diastereomers by well known methods, such as chiral-phase gas chromatography, chiral-phase high performance liquid chromatography, crystallizing the compound as a chiral salt complex, or crystallizing the compound in a chiral solvent. Enantiomers and diastereomers can also be obtained from diastereomerically- or enantiomerically-pure intermediates, reagents, and catalysts by well known asymmetric synthetic methods.

The compounds described herein are defined by their chemical structures and/or chemical names. Where a compound is referred to by both a chemical structure and a chemical name, and the chemical structure and the chemical name conflict, the chemical structure is determinative of the compound's identity.

When administered to a subject (e.g., a non-human animal for veterinary use or for improvement of livestock or to a human for clinical use), the compounds described herein are administered in an isolated form, or as the isolated form in a pharmaceutical composition. As used herein, “isolated” means that the compounds described herein are separated from other components of either: (a) a natural source, such as a plant or cell, preferably bacterial culture, or (b) a synthetic organic chemical reaction mixture. Preferably, the compounds described herein are purified via conventional techniques. As used herein, “purified” means that when isolated, the isolate contains at least 95%, preferably at least 98%, of a compound described herein by weight of the isolate either as a mixture of stereoisomers, or as a diastereomeric or enantiomeric pure isolate.

Only those choices and combinations of substituents that result in a stable structure are contemplated. Such choices and combinations will be apparent to those of ordinary skill in the art and may be determined without undue experimentation.

The invention can be understood more fully by reference to the following detailed description and illustrative examples, which are intended to exemplify non-limiting embodiments of the invention.

The methods described herein utilize triazolone compounds listed in Tables 1 or 2, or a compound represented by Formulae (I) or (Ia):

or a tautomer, or a pharmaceutically acceptable salt thereof, wherein:

-   -   Z is OH, SH, or NH₂;     -   X is CR₄ or N;     -   R₁ is —H, —OH, —SH, an optionally substituted alkyl, an         optionally substituted alkenyl, an optionally substituted         alkynyl, an optionally substituted cycloalkyl, an optionally         substituted cycloalkenyl, an optionally substituted         heterocyclyl, an optionally substituted aryl, an optionally         substituted heteroaryl, an optionally substituted aralkyl, an         optionally substituted heteraralkyl, halo, cyano, nitro,         guanidino, a haloalkyl, a heteroalkyl, an alkoxy or cycloalkoxy,         a haloalkoxy, —NR₁₀R₁₁, —OR₇, —C(O)R₇, —C(O)OR₇, —C(S)R₇,         —C(O)SR₇, —C(S)SR₇, —C(S)OR₇, —C(S)NR₁₀R₁₁, —C(NR₈)OR₇,         —C(NR₈)R₇, —C(NR₈)NR₁₀R₁₁, —C(NR₈)SR₇, —OC(O)R₇, —OC(O)OR₇,         —OC(S)OR₇, —OC(NRS)OR₇, —SC(O)R₇, —SC(O)OR₇, —SC(NR₈)OR₇,         —OC(S)R₇, —SC(S)R₇, —SC(S)OR₇, —OC(O)NR₁₀R₁₁, —OC(S)NR₁₀R₁₁,         —OC(NR₈)NR₁₀R₁₁, —SC(O)NR₁₀R₁₁, —SC(NR₈)NR₁₀R₁₁, —SC(S)NR₁₀R₁₁,         —OC(NR₈)R₇, —SC(NR₈)R₇, —C(O)NR₁₀R₁₁, —NR₈C(O)R₇, —NR₇C(S)R₇,         —NR₇C(S)OR₇, —NR₇C(NR₈)R₇, —NR₇C(O)OR₇, —NR₇C(NR₈)OR₇,         —NR₇C(O)NR₁₀R₁₁, —NR₇C(S)NR₁₀R₁₁, —NR₇C(NR₈)NR₁₀R₁₁, —SR₇,         —S(O)_(p)R₇, —OS(O)_(p)R₇, —OS(O)_(p)OR₇, —OS(O)_(p)NR₁₀R₁₁,         —S(O)_(p)OR₇, —NR₈S(O)_(p)R₇, —NR₇S(O)_(p)NR₁₀R₁₁,         —NR₇S(O)_(p)OR₇, —S(O)_(p)NR₁₀R₁₁, —SS(O)_(p)R₇, —SS(O)_(p)OR₇,         —SS(O)_(p)NR₁₀R₁₁, —OP(O)(OR₇)₂, or —SP(O)(OR₇)₂;     -   R₂ is —H, —OH, —SH, —NR₇H, —OR₁₅, —SR₁₅, —NHR₁₅, —O(CH₂)_(m)OH,         —O(CH₂)_(m)SH, —O(CH₂)_(m)NR₇H, —S(CH₂)_(m)OH, —S(CH₂)_(m)SH,         —S(CH₂)_(m)NR₇H, —OC(O)NR₁₀R₁₁, —SC(O)NR₁₀R₁₁, —NR₇C(O)NR₁₀R₁₁,         —OC(O)R₇, —SC(O)R₇, —NR₇C(O)R₇, —OC(O)OR₇, —SC(O)OR₇,         —NR₇C(O)OR₇, —OCH₂C(O)R₇, —SCH₂C(O)R₇, —NR₇CH₂C(O)R₇,         —OCH₂C(O)OR₇, —SCH₂C(O)OR₇, —NR₇CH₂C(O)OR₇, —OCH₂C(O)NR₁₀R₁₁,         —SCH₂C(O)NR₁₀R₁₁, —NR₇CH₂C(O)NR₁₀R₁₁, —OS(O)_(p)R₇,         —SS(O)_(p)R₇, —NR₇S(O)_(p)R₇, —OS(O)_(p)NR₁₀R₁₁,         —SS(O)_(p)NR₁₀R₁₁, —NR₇S(O)_(p)NR₁₀R₁₁, —OS(O)_(p)OR₇,         —SS(O)_(p)OR₇, —NR₇S(O)_(p)OR₇, —OC(S)R₇, —SC(S)R₇, —NR₇C(S)R₇,         —OC(S)OR₇, —SC(S)OR₇, —NR₇C(S)OR₇, —OC(S)NR₁₀R₁₁, —SC(S)NR₁₀R₁₁,         —NR₇C(S)NR₁₀R₁₁, —OC(NR₈)R₇, —SC(NR₈)R₇, —NR₇C(NR₈)R₇,         —OC(NR₈)OR₇, —SC(NR₈)OR₇, —NR₇C(NR₈)OR₇, —OC(NR₈)NR₁₀R₁₁,         —SC(NR₈)NR₁₀R₁₁, or —NR₇C(NR₈)NR₁₀R₁₁;     -   R₃ is —H, an optionally substituted alkyl, an optionally         substituted alkenyl, an optionally substituted alkynyl, an         optionally substituted cycloalkyl, an optionally substituted         cycloalkenyl, an optionally substituted heterocyclyl, an         optionally substituted aryl, an optionally substituted         heteroaryl, an optionally substituted aralkyl, an optionally         substituted heteraralkyl, hydroxyalkyl, alkoxyalkyl, a         haloalkyl, a heteroalkyl, —C(O)R₇, —(CH₂)_(m)C(O)OR₇, —C(O)OR₇,         —OC(O)R₇, —C(O)NR₁₀R₁₁, —S(O)_(p)R₇, —S(O)_(p)OR₇, or         —S(O)_(p)NR₁₀R₁₁;     -   R₄ is —H, —OH, an optionally substituted alkyl, an optionally         substituted alkenyl, an optionally substituted alkynyl, an         optionally substituted cycloalkyl, an optionally substituted         cycloalkenyl, an optionally substituted heterocyclyl, an         optionally substituted aryl, an optionally substituted         heteroaryl, an optionally substituted aralkyl, an optionally         substituted heteraralkyl, hydroxyalkyl, alkoxyalkyl, halo,         cyano, nitro, guanidino, a haloalkyl, a heteroalkyl, —C(O)R₇,         —C(O)OR₇, —OC(O)R₇, —C(O)NR₁₀R₁₁, —NR₈C(O)R₇, —SR₇, —S(O)_(p)R₇,         —OS(O)_(p)R₇, —S(O)_(p)OR₇, —NR₈S(O)_(p)R₇, —S(O)_(p)NR₁₀R₁₁, or         R₃ and R₄ taken together with the carbon atoms to which they are         attached form an optionally substituted cycloalkenyl, an         optionally substituted aryl, an optionally substituted         heterocyclyl, or an optionally substituted heteroaryl;     -   R₇ and R₈, for each occurrence, are, independently, —H, an         optionally substituted alkyl, an optionally substituted alkenyl,         an optionally substituted alkynyl, an optionally substituted         cycloalkyl, an optionally substituted cycloalkenyl, an         optionally substituted heterocyclyl, an optionally substituted         aryl, an optionally substituted heteroaryl, an optionally         substituted aralkyl, or an optionally substituted heteraralkyl;     -   R₁₀ and R₁₁, for each occurrence, are independently —H, an         optionally substituted alkyl, an optionally substituted alkenyl,         an optionally substituted alkynyl, an optionally substituted         cycloalkyl, an optionally substituted cycloalkenyl, an         optionally substituted heterocyclyl, an optionally substituted         aryl, an optionally substituted heteroaryl, an optionally         substituted aralkyl, or an optionally substituted heteraralkyl;         or R₁₀ and R₁₁, taken together with the nitrogen to which they         are attached, form an optionally substituted heterocyclyl or an         optionally substituted heteroaryl;     -   R₁₅, for each occurrence, is independently, a lower alkyl;     -   p, for each occurrence, is, independently, 1 or 2; and     -   m, for each occurrence, is independently, 1, 2, 3, or 4.

In an embodiment, in formula (I) or (Ia), X is CR₄.

In another embodiment, in formula (I) or (Ia), X is N.

In another embodiment, in formula (I) or (Ia), R₁ may be —H, lower alkyl, lower alkoxy, lower cycloalkyl, or lower cycloalkoxy.

In another embodiment, in formula (I) or (Ia), R₁ may be —H, methyl, ethyl, propyl, isopropyl, cyclopropyl, methoxy, ethoxy, propoxy, or cyclopropoxy.

In another embodiment, in formula (I) or (Ia), R₃ may be —H, a lower alkyl, a lower cycloalkyl, —C(O)N(R₂₇)₂, or —C(O)OH, wherein R₂₇ may be —H or a lower alkyl.

In another embodiment, in formula (I) or (Ia), R₃ may be —H, methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, —C(O)OH, —(CH₂)_(m)C(O)OH, —CH₂OCH₃, —CH₂CH₂OCH₃, or —C(O)N(CH₃)₂.

In an embodiment, R₄ may be —H or a lower alkyl.

In another embodiment, in formula (I) or (Ia), R₄ may be —H, methyl, ethyl, propyl, isopropyl or cyclopropyl.

In another embodiment, in formula (I) or (Ia), R₁ may be —H, —OH, —SH, —NH₂, a lower alkoxy or a lower alkyl amino.

In another embodiment, in formula (I) or (Ia), R₁ may be —H, —OH, methoxy or ethoxy.

In another embodiment, in formula (I) or (Ia), Z is —OH.

In another embodiment, in formula (I) or (Ia), Z is —SH.

In another embodiment, in formula (I) or (Ia), R₂ may be —H, —OH, —SH, —NH₂, a lower alkoxy or a lower alkyl amino.

In another embodiment, in formula (I) or (Ia), R₂ may be —H, —OH, methoxy, or ethoxy.

In another embodiment, in formula (I) or (Ia), R1 may be —H, methyl, ethyl, propyl, isopropyl, cyclopropyl, methoxy, ethoxy, propoxy, or cyclopropoxy; R₃ may be —H, methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, —C(O)OH, —(CH₂)_(m)C(O)OH, —CH₂OCH₃, —CH₂CH₂OCH₃, or —C(O)N(CH₃)₂; R₄ may be —H, methyl, ethyl, propyl, isopropyl or cyclopropyl; R₂ may be —H, —OH, —SH, —NH₂, a lower alkoxy or a lower alkyl amino; and Z is OH.

In another embodiment, in formula (I) or (Ia), R₁ may be —H, methyl, ethyl, propyl, isopropyl, cyclopropyl, methoxy, ethoxy, propoxy, or cyclopropoxy; R₃ may be —H, methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, —C(O)OH, —(CH₂)_(m)C(O)OH, —CH₂OCH₃, —CH₂CH₂OCH₃, or —C(O)N(CH₃)₂; R₄ may be —H, methyl, ethyl, propyl, isopropyl or cyclopropyl; R₂ may be —H, —OH, —SH, —NH₂, a lower alkoxy or a lower alkyl amino; and Z is SH.

In another embodiment, the compound may be:

-   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1,3-dimethyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1,3-dimethyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-isopropyl-indol-4-yl)-5-hydroxy-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indazol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indazol-6-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxyphenyl)-4-(1-ethyl-indol-4-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxyphenyl)-4-(1-isopropyl-indol-4-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxyphenyl)-4-(indol-4-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxyphenyl)-4-(1-methoxyethyl-indol-4-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1-isopropyl-indol-4-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxyphenyl)-4-(1-dimethylcarbamoyl-indol-4-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1-propyl-indol-4-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1,2,3-trimethyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(2,3-dimethyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1-acetyl-2,3-dimethyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1-propyl-2,3-dimethyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1-n-butyl-indol-4-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1-n-pentyl-indol-4-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1-n-hexyl-indol-4-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-cyclopropyl-phenyl)-4-(1-(1-methylcyclopropyl)-indol-4-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-cyclopropyl-phenyl)-4-(1,2,3-trimethyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1-methyl-3-ethyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1,3-dimethyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1-methyl-3-isopropyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1,2-dimethyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(N-methyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1,3-dimethyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-cyclopropyl-phenyl)-4-(1,3-dimethyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-cyclopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1H-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1,2-dimethyl-indol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-ethyl-indol-5-yl)-5-mercapto-[1,2,4]triazole,     or -   3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-propyl-indol-5-yl)-5-mercapto-[1,2,4]triazole,     or a tautomer, or a pharmaceutically acceptable salt thereof.

In another embodiment, the compound may be:

-   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1-ethyl-benzimidazol-4-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1-ethyl-benzimidazol-4-yl)-5-mercapto-[1,2,4]triazole     HCL salt, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(2-methyl-3-ethyl-benzimidazol-5-yl)-5-mercapto-[1,2,4]triazole, -   3-(2,4-dihydroxy-5-ethyl-phenyl)-4-(1-ethyl-2-methyl-benzimidazol-5-yl)-5-mercapto-[1,2,4]triazole,     or -   3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-2-trifluoromethyl-benzimidazol-5-yl)-5-mercapto-[1,2,4]triazole,     or a tautomer, or a pharmaceutically acceptable salt thereof.

In another embodiment, the compound may be:

-   5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl     dihydrogen phosphate, -   sodium     5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl     phosphate, -   2-(3,4-dimethoxyphenethyl)-5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)phenyl     dihydrogen phosphate, -   5-hydroxy-2-isopropyl-4-(5-mercapto-4-(4-methoxybenzyl)-4H-1,2,4-triazol-3-yl)phenyl     dihydrogen phosphate, -   5-hydroxy-4-(5-hydroxy-4-(4-methoxybenzyl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl     dihydrogen phosphate, -   4-(4-(1,3-dimethyl-1H-indol-5-yl)-5-hydroxy-4H-1,2,4-triazol-3-yl)-2-ethyl-5-hydroxyphenyl     dihydrogen phosphate, or a tautomer, or a pharmaceutically     acceptable salt thereof.

Hsp90 inhibitory compounds, as well as tautomers or pharmaceutically acceptable salts thereof that may be used in the methods described herein are depicted in Tables 1 or 2.

TABLE 1 STRUCTURE TAUTOMERIC STRUCTURE NAME 1

3-(2,4-DIHYDROXY-5- ISOPROPYL-PHENYL)-4-(1- METHYL-INDOL-5-YL)-5- HYDROXY-[1,2,4]TRIAZOLE 2

3-(2,4-DIHYDROXYPHENYL)-4- (1-ETHYL-INDOL-4-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 3

3-(2,4-DIHYDROXY-PHENYL)-4- (2,3-DIMETHYL-1H-INDOL-4- YL)-5-MERCAPTO-[1,2,4] TRIAZOLE 4

3-(2,4-DIHYDROXYPHENYL)-4- (1-ISOPROPYL-INDOL-4-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 5

3-(2,4-DIHYDROXY-PHENYL)-4- (INDOL-4-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 6

3-(2,4-DIHYDROXY-PHENYL)-4- [1-(2-METHOXYETHOXY)- INDOL-4-YL]-5-MERCAPTO- [1,2,4] TRIAZOLE 7

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-ISOPROPYL- INDOL-4-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 8

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-[1-(DIMETHYL- CARBAMOYL)-INDOL-4-YL]-5- MERCAPTO-[1,2,4] TRIAZOLE 9

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-ETHYL- BENZOIMIDAZOL-4-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 10

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1,2,3-TRIMETHYL- INDOL-5-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 11

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-ISOPROPYL- INDOL-3-YL)-5-HYDROXY- [1,2,4] TRIAZOLE 12

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-ISOPROPYL- INDOL-4-YL)-5-AMINO-[1,2,4] TRIAZOLE 15

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-ISOPROPYL- INDOL-4-YL)-5-UREIDO-[1,2,4] TRIAZOLE 16

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-METHYL-INDOL- 4-YL)-5-CARBAMOYLOXY- [1,2,4] TRIAZOLE 17

3-(2,4-DIHYDROXY-PHENYL)-4- (1-METHYL-2-CHLORO-INDOL- 4-YL)-5-CARBAMOYLOXY- [1,2,4] TRIAZOLE 18

3-(2,4-DIHYDROXY-5- METHOXY-PHENYL)-4-(1- ISOPROPYL-BENZOIMIDAZOL- 4-YL)-5-(SULFAMOYLAMINO)- [1,2,4] TRIAZOLE 20

3-(2,4-DIHYDROXY-5- METHOXY-PHENYL)-4-(1- ISOPROPYL-BENZOIMIDAZOL- 4-YL)-5-(SULFAMOYLOXY)- [1,2,4] TRIAZOLE 21

3-(2-HYDROXY-4- ETHOXYCARBONYOXY-5- METHOXY-PHENYL)-4-(1- ISOPROPYL-BENZOIMIDAZOL- 4-YL)-5-HYDROXY-[1,2,4] TRIAZOLE 22

3-[2-HYDROXY-4- ISOBUTYRYLOXY-5-ETHYL- PHENYL]-4-(1-METHYL-BENZO- IMIDAZOL-4-YL)-5-HYDROXY- [1,2,4] TRIAZOLE 23

3-(2,4-DIHYDROXY-PHENYL)-4- (1-DIMETHYLCARBAMOYL- INDOL-4-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 24

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(2,3-DIMETHYL- INDOL-5-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 25

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-ETHYL-1H- BENZOIMIDAZOL-4-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE, HCL SALT 26

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-ISOPROPYL-7- METHOXY-INDOL-4-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 27

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-PROPYL-INDOL- 4-YL)-5-MERCAPTO-[1,2,4] TRIAZOLE 28

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-ACETYL-2,3- DIMETHYL-INDOL-5-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 29

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(2-METHYL-3- ETHYL-BENZIMIDAZOL-5-YL)- 5-MERCAPTO-[1,2,4] TRIAZOLE 30

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-ETHYL-2- METHYL-BENZIMIDAZOL-5- YL)-5-MERCAPTO-[1,2,4] TRIAZOLE 31

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-PROPYL-2,3- DIMETHYL-INDOL-5-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 34

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-N-BUTYL-INDOL- 4-YL)-5-MERCAPTO-[1,2,4] TRIAZOLE 35

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-N-PENTYL- INDOL-4-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 36

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-N-HEXYL-INDOL- 4-YL)-5-MERCAPTO-[1,2,4] TRIAZOLE 37

3-(2,4-DIHYDROXY-5- CYCLOPROPYL-PHENYL)-4-(1- (1-METHYLCYCLOPROPYL)- INDOL-4-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 38

3-(2,4-DIHYDROXY-5- CYCLOPROPYL-PHENYL)-4-(1- ISOPROPYL-7-METHOXY- INDOL-4-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 39

3-(2,4-DIHYDROXY-5- CYCLOPROPYL-PHENYL)-4- (1,2,3-TRIMETHYL-INDOL-5- YL)-5-MERCAPTO-[1,2,4] TRIAZOLE 40

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-ISOPROPYL-7- METHOXY-INDOL-4-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE DISODIUM SALT 41

3-(2,4-DIHYDROXY-5-TERT- BUTYL-PHENYL)-4-(1- ISOPROPYL-7-METHOXY- INDOL-4-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 42

3-(2,4-DIHYDROXY-5- CYCLOPROPYL-PHENYL)-4-(1- PROPYL-7-METHOXY-INDOL-4- YL)-5-MERCAPTO-[1,2,4] TRIAZOLE 43

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-METHYL-3- ETHYL-INDOL-5-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 44

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1,3-DIMETHYL- INDOL-5-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 45

3-(2,4-DIHYDROXY-5- ISOPROPYL-PHENYL)-4-(1- ISOPROPYL-7-METHOXY- INDOL-4-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 46

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-METHYL-3- ISOPROPYL-INDOL-5-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 48

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-ISOPROPYL-7- HYDROXY-INDOL-4-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 49

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1-ISOPROPYL-7- ETHOXY-INDOL-4-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 50

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1,2-DIMETHYL- INDOL-5-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 51

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(N-METHYL- INDOL-5-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 55

3-(2,4-DIHYDROXY-5- ISOPROPYL-PHENYL)-4-(1,3- DIMETHYL-INDOL-5-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 56

3-(2,4-DIHYDROXY-5- CYCLOPROPYL-PHENYL)-4-(1,3- DIMETHYL-INDOL-5-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 57

3-(2,4-DIHYDROXY-5-ETHYL- PHENYL)-4-(1,3-DIMETHYL- INDOL-5-HYDROXY- [1,2,4] TRIAZOLE 58

3-(2,4-DIHYDROXY-5- ISOPROPYL-PHENYL)-4-(N- METHYL-INDOL-5-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 59

3-(2,4-DIHYDROXY-5- ISOPROPYL-PHENYL)-4-(1,2- DIMETHYL-INDOL-5-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 60

3-(2,4-DIHYDROXY-5- ISOPROPYL-PHENYL)-4-(1,3- DIMETHYL-INDOL-5-YL)-5- HYDROXY-[1,2,4] TRIAZOLE 62

3-(2,4-DIHYDROXY-5- ISOPROPYL-PHENYL)-4-(1H- INDOL-5-YL)-5-MERCAPTO- [1,2,4] TRIAZOLE 63

3-(2,4-DIHYDROXY-5- ISOPROPYL-PHENYL)-4-(1- ETHYL-INDOL-5-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 64

3-(2,4-DIHYDROXY-5- ISOPROPYL-PHENYL)-4-(1- PROPYL-INDOL-5-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 65

3-(2,4-DIHYDROXY-5- ISOPROPYL-PHENYL)-4-(1- METHYL-2- TRIFLUOROMETHYL- BENZIMIDAZOL-5-YL)-5- MERCAPTO-[1,2,4] TRIAZOLE 66

3-(2,4-DIHYDROXY-5- ISOPROPYL-PHENYL)-4-(1- ISOPROPYL-INDOL-4-YL)-5- HYDROXY-[1,2,4] TRIAZOLE

TABLE 2 Compounds according to Formula (Ia) NO. STRUCTURE TAUTOMERIC STRUCTURE NAME 1A

5-HYDROXY-4-(5- HYDROXY-4-(1- METHYL-1H-INDOL-5- YL)-4H-1,2,4-TRIAZOL- 3-YL)-2- ISOPROPYLPHENYL DIHYDROGEN PHOSPHATE 2A

SODIUM 5-HYDROXY-4- (5-HYDROXY-4-(1- METHYL-1H-INDOL-5- YL)-4H-1,2,4-TRIAZOL- 3-YL)-2- ISOPROPYLPHENYL PHOSPHATE 3A

2-(3,4- DIMETHOXY- PHENETHYL)-5- HYDROXY-4-(5- HYDROXY- 4-(1-METHYL-1H- INDOL-5 YL)-4H-1,2,4- TRIAZOL- 3-YL)PHENYL DIHYDROGEN PHOSPHATE 4A

4-(4-(1,3-DIMETHYL- 1H-INDOL-5-YL)-5- HYDROXY-4H-1,2,4- TRIAZOL-3-YL)-2- ETHYL-5- HYDROXYPHENYL DIHYDROGEN PHOSPHATE

The Hsp90 inhibitory compounds used in the disclosed combination methods can be prepared according to the procedures disclosed in U.S. Patent Publication No. 2006/0,167,070, and WO2009/023,211.

These triazolone compounds typically can form a tautomeric structure as shown below and as exemplified by the tautomeric structures shown in Tables 1 and 2:

In some embodiments, the present invention provides pharmaceutical combinations for the treatment, prophylaxis, and amelioration of proliferative disorders, such as cancer. In a specific embodiment, the combination comprises one or more Hsp90 inhibitors according to formulae (I) or (Ia), or a compound in Tables 1 or 2, or a tautomer or a pharmaceutically acceptable salt thereof in addition to a BRAF inhibitor.

In an embodiment, the combination includes a pharmaceutical composition or a single unit dosage form containing both an Hsp90 inhibitor and a BRAF inhibitor. Pharmaceutical combinations and dosage forms described herein comprise the two active ingredients in relative amounts and formulated in such a way that a given pharmaceutical combination or dosage form can be used to treat proliferative disorders, such as cancer. Preferred pharmaceutical combinations and dosage forms comprise a compound of formulae (I) or (Ia), or a compound in Tables 1 or 2, or a tautomer or pharmaceutically acceptable salt thereof, in combination with a BRAF inhibitor. In other embodiments, the Hsp90 inhibitor and the BRAF inhibitor may be in individual or separate pharmaceutical compositions, depending on the dosing schedules, preferred routes of administration, and available formulations of the two compounds. Optionally, these embodiments can also contain one or more additional therapeutic agents.

The pharmaceutical combinations described herein are formulated to be compatible with its intended route of administration. Examples of routes of administration include parenteral, e.g., intravenous, intradermal, subcutaneous, oral, intranasal (e.g., inhalation), transdermal (topical), transmucosal, and rectal administration. In a specific embodiment, the combination is formulated in accordance with routine procedures as a pharmaceutical composition adapted for intravenous, subcutaneous, intramuscular, oral, intranasal or topical administration to human beings. In an embodiment, the combination is formulated in accordance with routine procedures for subcutaneous administration to human beings.

In a specific embodiment, the combination therapy described herein comprises one or more compounds and at least one other therapy which has the same mechanism of action as the compounds. In another specific embodiment, the combination therapy described herein comprises one or more compounds described herein and at least one other therapy which has a different mechanism of action than the compounds. In certain embodiments, the combination therapies described herein improve the therapeutic effect of one or more triazolone compounds described herein by functioning together with the BRAF inhibitor to have an additive or synergistic effect. In certain embodiments, the combination therapies described herein reduce the side effects associated with the therapies. In certain embodiments, the combination therapies described herein reduce the effective dosage of one or more of the therapies.

In a specific embodiment, the combination comprising one or more triazolone compounds described herein is administered to a subject, preferably a human, to prevent, treat, manage, or ameliorate cancer, or one or more symptom thereof. In accordance with the invention, the pharmaceutical combinations described herein may also comprise one or more other agents being used, have been used, or are known to be useful in the treatment or amelioration of cancer, particularly breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, or colon cancer. The pharmaceutical combinations described herein utilize pharmaceutical compositions and dosage forms which comprise one or more excipients. Suitable excipients are well known to those skilled in the art of pharmacy.

The triazolone compounds described herein can be also formulated into or administered by controlled release means or by delivery devices that are well known to those of ordinary skill in the art. Examples include those described in U.S. Pat. Nos. 3,845,770; 3,916,899; 3,536,809; 3,598,123; and 4,008,719, 5,674,533, 5,059,595, 5,591,767, 5,120,548, 5,073,543, 5,639,476, 5,354,556, and 5,733,566.

In some embodiments, the present invention also provides a method of treating a proliferative disorder in a subject, comprising administering to the subject an effective amount of the combination of an Hsp90 inhibitor and a BRAF inhibitor as described herein. In an embodiment, the proliferative disorder is cancer. In one aspect of this embodiment, the cancer is breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, testicular tumor, ovarian cancer, lymphoma, leukemia, multiple myeloma, anaplastic thyroid carcinoma, papillary thyroid carcinoma, Barrett's esophageal carcinoma, or colon cancer. In an embodiment, the cancer is unresectable or metastatic melanoma. In an embodiment, the melanoma, or unrsectable melanoma, or metastatic melanoma has BRAF^(V600E) mutation.

Some of the disclosed methods can be also effective at treating subjects whose cancer has become “drug resistant” or “multi-drug resistant”. A cancer which initially responded to an anti-cancer drug becomes resistant to the anti-cancer drug when the anti-cancer drug is no longer effective in treating the subject with the cancer. For example, many tumors will initially respond to treatment with an anti-cancer drug by decreasing in size or even going into remission, only to develop resistance to the drug. “Drug resistant” tumors are characterized by a resumption of their growth and/or reappearance after having seemingly gone into remission, despite the administration of increased dosages of the anti-cancer drug. Cancers that have developed resistance to two or more anti-cancer drugs are said to be “multi-drug resistant”. For example, it is common for cancers to become resistant to three or more anti-cancer agents, often five or more anti-cancer agents and at times ten or more anti-cancer agents.

Other anti-proliferative or anti-cancer therapies may be combined with the compounds described herein to treat proliferative diseases and cancer. Other therapies or anti-cancer agents that may be used in combination with the inventive anti-cancer agents described herein include surgery, radiotherapy (including gamma-radiation, neutron beam radiotherapy, electron beam radiotherapy, proton therapy, brachytherapy, and systemic radioactive isotopes), endocrine therapy, biologic response modifiers (including interferons, interleukins, and tumor necrosis factor (TNF)), hyperthermia and cryotherapy, agents to attenuate any adverse effects (e.g., antiemetics), and other approved chemotherapeutic drugs.

The therapeutic agents of the combination therapies described herein can be administered sequentially or concurrently. In an embodiment, the administration of the Hsp90 inhibitor and the BRAF inhibitor are done concurrently. In another embodiment, the administration of the Hsp90 inhibitor and the BRAF inhibitor are done separately. In another embodiment, the administration of the Hsp90 inhibitor and the BRAF inhibitor are done sequentially. In an embodiment, the administration of the Hsp90 inhibitor and the BRAF inhibitor are done until the cancer is cured or stabilized or improved.

In an embodiment, the present method includes treating, managing, or ameliorating cancer, or one or more symptoms thereof, comprising administering to a subject in need thereof one or more compounds represented by the structural formulae (I) or (Ia) or a compound in Table 1 or Table 2, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®), wherein the cancer is breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, testicular tumor, ovarian cancer, lymphoma, leukemia, multiple myeloma, anaplastic thyroid carcinoma, papillary thyroid carcinoma, Barrett's esophageal carcinoma, or colon cancer. In an embodiment, the cancer is unresectable or metastatic melanoma. In an embodiment, the melanoma, or unrsectable melanoma, or metastatic melanoma has BRAF^(V600E) mutation. In an embodiment, the cancer has a KRAS mutation. In an embodiment, the cancer has an ALK mutation. In an embodiment, the cancer has a BRAF mutation.

In another embodiment, the method of treating a subject with cancer includes administering to the subject an effective amount of a triazolone compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with an effective amount of a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®).

In another embodiment, the method of treating a subject with cancer includes administering to the subject an effective amount of a triazolone compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with an effective amount of PLX-4032. In another embodiment, the method of treating a subject with cancer includes administering to the subject an amount of a triazolone compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with an amount of PLX-4032 to achieve a synergistic treatment effect. In an embodiment, PLX-4032 is administered orally at a dose of between about 200 mg to about 2000 mg. In an embodiment, PLX-4032 is administered at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg twice daily. In an embodiment, PLX-4032 is administered at a dose of about 480 mg twice daily. In an embodiment, PLX-4032 is administered at about 720 mg twice daily. In an embodiment, PLX-4032 is administered at about 960 mg twice daily. In an embodiment, the amount of the Hsp90 inhibitor is from about 2 m g/m² to about 260 mg/m². In an embodiment, the amount of the Hsp90 inhibitor is about 75 mg/m², about 85 mg/m², about 100 mg/m², about 110 mg/m², about 115 mg/m², about 120 mg/m², about 145 mg/m², about 150 mg/m², about 175 mg/m², about 180 mg/m², about 200 mg/m², about 215 mg/m² or about 260 mg/m². In an embodiment, the Hsp90 inhibitor is administered IV once weekly or twice weekly. In any of the above embodiments, the cancer may be unresectable or metastatic melanoma. In any of the above embodiments, the melanoma, or unrsectable melanoma, or metastatic melanoma may have a BRAF^(V600E) mutation. In any one of the above embodiments, the cancer may have a KRAS mutation. In any one of the above embodiments, the cancer may have an ALK mutation. In any one of the above embodiments, the cancer may have a BRAF mutation.

In another embodiment, the method of treating a subject with cancer includes administering to the subject an effective amount of a triazolone compound of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with an effective amount of a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®).

In another embodiment, the method of treating a subject with cancer includes administering to the subject an effective amount of a triazolone compound of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with an effective amount of PLX-4032. In another embodiment, the method of treating a subject with cancer includes administering to the subject an amount of a triazolone compound of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with an amount of PLX-4032 to achieve a synergistic treatment effect. In an embodiment, PLX-4032 is administered orally at a dose of between about 200 mg to about 2000 mg. In an embodiment, PLX-4032 is administered at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg twice daily. In an embodiment, PLX-4032 is administered at a dose of about 480 mg twice daily. In an embodiment, PLX-4032 is administered at about 720 mg twice daily. In an embodiment, PLX-4032 is administered at about 960 mg twice daily. In an embodiment, the amount of the Hsp90 inhibitor is from about 2 mg/m² to about 260 mg/m². In an embodiment, the amount of the Hsp90 inhibitor is about 75 mg/m², about 85 mg/m², about 100 mg/m², about 110 mg/m², about 115 mg/m², about 120 mg/m², about 145 mg/m², about 150 mg/m², about 175 mg/m², about 180 mg/m², about 200 mg/m², about 215 mg/m² or about 260 mg/m². In an embodiment, the Hsp90 inhibitor is administered IV once weekly or twice weekly. In any of the above embodiments, the cancer may be unresectable or metastatic melanoma. In any of the above embodiments, the melanoma, or unrsectable melanoma, or metastatic melanoma may have a BRAF^(V600E) mutation. In any one of the above embodiments, the cancer may have a KRAS mutation. In any one of the above embodiments, the cancer may have an ALK mutation. In any one of the above embodiments, the cancer may have a BRAF mutation.

In another embodiment, the method of treating a subject with cancer includes administering to the subject an effective amount of a triazolone compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®), wherein the cancer is breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, testicular tumor, ovarian cancer, lymphoma, leukemia, multiple myeloma, anaplastic thyroid carcinoma, papillary thyroid carcinoma, Barrett's esophageal carcinoma, or colon cancer. In an embodiment, the cancer is unresectable or metastatic melanoma. In an embodiment, the melanoma, or unrsectable melanoma, or metastatic melanoma has a BRAF^(V600E) mutation. In an embodiment, the cancer has a KRAS mutation. In an embodiment, the cancer has an ALK mutation. In an embodiment, the cancer has a BRAF mutation.

In another embodiment, the method of treating a subject with cancer includes administering to the subject an effective amount of a triazolone compound of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®), wherein the cancer is breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, testicular tumor, ovarian cancer, lymphoma, leukemia, multiple myeloma, anaplastic thyroid carcinoma, papillary thyroid carcinoma, Barrett's esophageal carcinoma, or colon cancer. In an embodiment, the cancer is unresectable or metastatic melanoma. In an embodiment, the melanoma, or unrsectable melanoma, or metastatic melanoma has a BRAF^(V600E) mutation. In an embodiment, the cancer has a KRAS mutation. In an embodiment, the cancer has an ALK mutation. In an embodiment, the cancer has a BRAF mutation.

In yet another embodiment, the method of treating a subject with cancer, wherein the subject is being or has been treated with a chemotherapeutic agent, includes administering to the subject an effective amount of a triazolone compound represented by the structural formulae (I) or (Ia) or a compound in Table 1 or Table 2, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®).

In an embodiment, the method of treating a subject with cancer, wherein the subject is being or has been treated with a chemotherapeutic agent, includes administering to the subject an effective amount of a triazolone compound represented by the structural formulae (I) or (Ia) or a compound in Table 1 or Table 2, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®), wherein the cancer is breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, testicular tumor, ovarian cancer, lymphoma, leukemia, multiple myeloma, anaplastic thyroid carcinoma, papillary thyroid carcinoma, Barrett's esophageal carcinoma, or colon cancer. In an embodiment, the cancer is unresectable or metastatic melanoma. In an embodiment, the melanoma, or unrsectable melanoma, or metastatic melanoma has BRAF^(V600E) mutation. In an embodiment, the cancer has a KRAS mutation. In an embodiment, the cancer has an ALK mutation. In an embodiment, the cancer has a BRAF mutation.

In another embodiment, the method of treating a subject with cancer, wherein the subject is being or has been treated with a chemotherapeutic agent, includes administering to the subject an effective amount of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®).

In another embodiment, the method of treating a subject with cancer, wherein the subject is being or has been treated with a chemotherapeutic agent, includes administering to the subject an effective amount of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with PLX-4032. In an embodiment, PLX-4032 is administered orally at a dose of between about 200 mg to about 2000 mg. In an embodiment, PLX-4032 is administered at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg twice daily. In an embodiment, PLX-4032 is administered at a dose of about 480 mg twice daily. In an embodiment, PLX-4032 is administered at about 720 mg twice daily. In an embodiment, PLX-4032 is administered at about 960 mg twice daily. In an embodiment, the amount of the Hsp90 inhibitor is from about 2 mg/m² to about 260 mg/m². In an embodiment, the amount of the Hsp90 inhibitor is about 75 mg/m², about 85 mg/m², about 100 mg/m², about 110 mg/m², about 115 mg/m², about 120 mg/m², about 145 mg/m², about 150 mg/m², about 175 mg/m², about 180 mg/m², about 200 mg/m², about 215 mg/m² or about 260 mg/m². In an embodiment, the Hsp90 inhibitor is administered IV once weekly or twice weekly. In any of the above embodiments, the cancer may be unresectable or metastatic melanoma. In any of the above embodiments, the melanoma, or unrsectable melanoma, or metastatic melanoma may have a BRAF^(V600E) mutation. In any one of the above embodiments, the cancer may have a KRAS mutation. In any one of the above embodiments, the cancer may have an ALK mutation. In any one of the above embodiments, the cancer may have a BRAF mutation.

In another embodiment, the method of treating a subject with cancer, wherein the subject is being or has been treated with a chemotherapeutic agent, includes administering to the subject an effective amount of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®).

In another embodiment, the method of treating a subject with cancer, wherein the subject is being or has been treated with a chemotherapeutic agent, includes administering to the subject an effective amount of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with PLX-4032. In an embodiment, PLX-4032 is administered orally at a dose of between about 200 mg to about 2000 mg. In an embodiment, PLX-4032 is administered at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg twice daily. In an embodiment, PLX-4032 is administered at a dose of about 480 mg twice daily. In an embodiment, PLX-4032 is administered at about 720 mg twice daily. In an embodiment, PLX-4032 is administered at about 960 mg twice daily. In an embodiment, the amount of the Hsp90 inhibitor is from about 2 mg/m² to about 260 mg/m². In an embodiment, the amount of the Hsp90 inhibitor is about 75 mg/m², about 85 mg/m², about 100 mg/m², about 110 mg/m², about 115 mg/m², about 120 mg/m², about 145 mg/m², about 150 mg/m², about 175 mg/m², about 180 mg/m², about 200 mg/m², about 215 mg/m² or about 260 mg/m². In an embodiment, the Hsp90 inhibitor is administered IV once weekly or twice weekly. In any of the above embodiments, the cancer may be unresectable or metastatic melanoma. In any of the above embodiments, the melanoma, or unrsectable melanoma, or metastatic melanoma may have a BRAF^(V600E) mutation. In any one of the above embodiments, the cancer may have a KRAS mutation. In any one of the above embodiments, the cancer may have an ALK mutation. In any one of the above embodiments, the cancer may have a BRAF mutation.

In an embodiment, the method of treating a subject with cancer, wherein the subject is being or has been treated with a chemotherapeutic agent, includes administering to the subject an effective amount of a triazolone compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®), wherein the cancer is breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, testicular tumor, ovarian cancer, lymphoma, leukemia, multiple myeloma, anaplastic thyroid carcinoma, papillary thyroid carcinoma, Barrett's esophageal carcinoma, or colon cancer. In an embodiment, the cancer is unresectable or metastatic melanoma. In an embodiment, the melanoma, or unrsectable melanoma, or metastatic melanoma has a BRAF^(V600E) mutation. In an embodiment, the cancer has a KRAS mutation. In an embodiment, the cancer has an ALK mutation. In an embodiment, the cancer has a BRAF mutation.

In an embodiment, the method of treating a subject with cancer, wherein the subject is being or has been treated with a chemotherapeutic agent, includes administering to the subject an effective amount of a triazolone compound of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®), wherein the cancer is breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, testicular tumor, ovarian cancer, lymphoma, leukemia, multiple myeloma, anaplastic thyroid carcinoma, papillary thyroid carcinoma, Barrett's esophageal carcinoma, or colon cancer. In an embodiment, the cancer is unresectable or metastatic melanoma. In an embodiment, the melanoma, or unrsectable melanoma, or metastatic melanoma has a BRAF^(V600E) mutation. In an embodiment, the cancer has a KRAS mutation. In an embodiment, the cancer has an ALK mutation. In an embodiment, the cancer has a BRAF mutation.

In an embodiment, the method of treating a subject with cancer, wherein the subject has proven refractory to other therapies but is no longer on these therapies, includes administering to the subject an effective amount of a triazolone compound represented by the structural formulae (I) or (Ia) or a compound in Table 1 or Table 2, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®), wherein the cancer is breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, testicular tumor, ovarian cancer, lymphoma, leukemia, multiple myeloma, anaplastic thyroid carcinoma, papillary thyroid carcinoma, Barrett's esophageal carcinoma, or colon cancer. In an embodiment, the cancer is unresectable or metastatic melanoma. In an embodiment, the melanoma, or unrsectable melanoma, or metastatic melanoma has a BRAF^(V600E) mutation. In an embodiment, the cancer has a KRAS mutation. In an embodiment, the cancer has an ALK mutation. In an embodiment, the cancer has a BRAF mutation.

In another embodiment, the method of treating a subject with cancer, wherein the subject has proven refractory to other therapies but is no longer on these therapies, includes administering to the subject an effective amount of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®).

In another embodiment, the method of treating a subject with cancer, wherein the subject has proven refractory to other therapies but is no longer on these therapies, includes administering to the subject an effective amount of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with PLX-4032. In an embodiment, PLX-4032 is administered orally at a dose of between about 200 mg to about 2000 mg. In an embodiment, PLX-4032 is administered at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg twice daily. In an embodiment, PLX-4032 is administered at a dose of about 480 mg twice daily. In an embodiment, PLX-4032 is administered at about 720 mg twice daily. In an embodiment, PLX-4032 is administered at about 960 mg twice daily. In an embodiment, the amount of the Hsp90 inhibitor is from about 2 mg/m² to about 260 mg/m². In an embodiment, the amount of the Hsp90 inhibitor is about 75 mg/m², about 85 mg/m², about 100 mg/m², about 110 mg/m², about 115 mg/m², about 120 mg/m², about 145 mg/m², about 150 mg/m², about 175 mg/m², about 180 mg/m², about 200 mg/m², about 215 mg/m² or about 260 mg/m². In an embodiment, the Hsp90 inhibitor is administered IV once weekly or twice weekly. In any of the above embodiments, the cancer may be unresectable or metastatic melanoma. In any of the above embodiments, the melanoma, or unrsectable melanoma, or metastatic melanoma may have a BRAF^(V600E) mutation. In any one of the above embodiments, the cancer may have a KRAS mutation. In any one of the above embodiments, the cancer may have an ALK mutation. In any one of the above embodiments, the cancer may have a BRAF mutation.

In another embodiment, the method of treating a subject with cancer, wherein the subject has proven refractory to other therapies but is no longer on these therapies, includes administering to the subject an effective amount of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®).

In another embodiment, the method of treating a subject with cancer, wherein the subject has proven refractory to other therapies but is no longer on these therapies, includes administering to the subject an effective amount of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with PLX-4032. In an embodiment, PLX-4032 is administered orally at a dose of between about 200 mg to about 2000 mg. In an embodiment, PLX-4032 is administered at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg. In an embodiment, PLX-4032 is administered orally at a dose from about 480 mg to about 960 mg twice daily. In an embodiment, PLX-4032 is administered at a dose of about 480 mg twice daily. In an embodiment, PLX-4032 is administered at about 720 mg twice daily. In an embodiment, PLX-4032 is administered at about 960 mg twice daily. In an embodiment, the amount of the Hsp90 inhibitor is from about 2 mg/m² to about 260 mg/m². In an embodiment, the amount of the Hsp90 inhibitor is about 75 mg/m², about 85 mg/m², about 100 mg/m², about 110 mg/m², about 115 mg/m², about 120 mg/m², about 145 mg/m², about 150 mg/m², about 175 mg/m², about 180 mg/m², about 200 mg/m², about 215 mg/m² or about 260 mg/m². In an embodiment, the Hsp90 inhibitor is administered IV once weekly or twice weekly. In any of the above embodiments, the cancer may be unresectable or metastatic melanoma. In any of the above embodiments, the melanoma, or unrsectable melanoma, or metastatic melanoma may have a BRAF^(V600E) mutation. In any one of the above embodiments, the cancer may have a KRAS mutation. In any one of the above embodiments, the cancer may have an ALK mutation. In any one of the above embodiments, the cancer may have a BRAF mutation.

In an embodiment, the method of treating a subject with cancer, wherein the subject has proven refractory to other therapies but is no longer on these therapies, includes administering to the subject an effective amount of a triazolone compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®), wherein the cancer is breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, testicular tumor, ovarian cancer, lymphoma, leukemia, multiple myeloma, anaplastic thyroid carcinoma, papillary thyroid carcinoma, Barrett's esophageal carcinoma, or colon cancer. In an embodiment, the cancer is unresectable or metastatic melanoma. In an embodiment, the melanoma, or unrsectable melanoma, or metastatic melanoma has a BRAF^(V600E) mutation. In an embodiment, the cancer has a KRAS mutation. In an embodiment, the cancer has an ALK mutation. In an embodiment, the cancer has a BRAF mutation.

In an embodiment, the method of treating a subject with cancer, wherein the subject has proven refractory to other therapies but is no longer on these therapies, includes administering to the subject an effective amount of a triazolone compound of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®), wherein the cancer is breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, testicular tumor, ovarian cancer, lymphoma, leukemia, multiple myeloma, anaplastic thyroid carcinoma, papillary thyroid carcinoma, Barrett's esophageal carcinoma, or colon cancer. In an embodiment, the cancer is unresectable or metastatic melanoma. In an embodiment, the melanoma, or unrsectable melanoma, or metastatic melanoma has a BRAF^(V600E) mutation. In an embodiment, the cancer has a KRAS mutation. In an embodiment, the cancer has an ALK mutation. In an embodiment, the cancer has a BRAF mutation.

In a further embodiment, the method includes inhibiting the growth of a cancer or tumor cell comprising the steps of: (a) contacting the cell with an effective amount of a compound of formulae (I) or (Ia) or a compound in Table (1) or Table (2), or tautomer or a pharmaceutically acceptable salt thereof; and (b) exposing the cell to an effective amount of a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®).

In a further embodiment, the method includes inhibiting the growth of a cancer or tumor cell comprising the steps of: (a) contacting the cell with an effective amount of a compound of -(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof; and (b) exposing the cell to an effective amount of a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®).

In a further embodiment, the method includes inhibiting the growth of a cancer or tumor cell comprising the steps of: (a) contacting the cell with an effective amount of a compound of -(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof; and (b) exposing the cell to an effective amount of PLX-4032.

In a further embodiment, the method includes inhibiting the growth of a cancer or tumor cell comprising the steps of: (a) contacting the cell with an effective amount of a compound of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or tautomer or a pharmaceutically acceptable salt thereof; and (b) exposing the cell to an effective amount of a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®).

In a further embodiment, the method includes inhibiting the growth of a cancer or tumor cell comprising the steps of: (a) contacting the cell with an effective amount of a compound of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or tautomer or a pharmaceutically acceptable salt thereof; and (b) exposing the cell to an effective amount of PLX-4032.

In general, the recommended daily dose range of a triazolone compound for the conditions described herein lie within the range of from about 0.01 mg to about 1000 mg per day, given as a single once-a-day dose preferably as divided doses throughout a day. In an embodiment, the daily dose is administered twice daily in equally divided doses. Specifically, a daily dose range should be from about 5 mg to about 500 mg per day, more specifically, between about 10 mg and about 200 mg per day. In managing the patient, the therapy should be initiated at a lower dose, perhaps about 1 mg to about 25 mg, and increased if necessary up to about 200 mg to about 1000 mg per day as either a single dose or divided doses, depending on the patient's global response. It may be necessary to use dosages of the active ingredient outside the ranges disclosed herein in some cases, as will be apparent to those of ordinary skill in the art. Furthermore, it is noted that the clinician or treating physician will know how and when to interrupt, adjust, or terminate therapy in conjunction with individual patient response.

Different therapeutically effective amounts may be applicable for different cancers, as will be readily known by those of ordinary skill in the art. Similarly, amounts sufficient to prevent, manage, treat or ameliorate such cancers, but insufficient to cause, or sufficient to reduce, adverse effects associated with the triazolone compounds described herein are also encompassed by the above described dosage amounts and dose frequency schedules. Further, when a patient is administered multiple dosages of a triazolone compound described herein, not all of the dosages need be the same. For example, the dosage administered to the patient may be increased to improve the prophylactic or therapeutic effect of the compound or it may be decreased to reduce one or more side effects that a particular patient is experiencing.

In a specific embodiment, the dosage of the composition comprising a triazolone compound described herein administered to prevent, treat, manage, or ameliorate cancer, or one or more symptoms thereof in a patient is 150 μg/kg, preferably 250 μg/kg, 500 μg/kg, 1 mg/kg, 5 mg/kg, 10 mg/kg, 25 mg/kg, 50 mg/kg, 75 mg/kg, 100 mg/kg, 125 mg/kg, 150 mg/kg, or 200 mg/kg or more of a patient's body weight. In another embodiment, the dosage of the composition comprising a compound described herein administered to prevent, treat, manage, or ameliorate cancer, or one or more symptoms thereof in a patient is a unit dose of 0.1 mg to 20 mg, 0.1 mg to 15 mg, 0.1 mg to 12 mg, 0.1 mg to 10 mg, 0.1 mg to 8 mg, 0.1 mg to 7 mg, 0.1 mg to 5 mg, 0.1 to 2.5 mg, 0.25 mg to 20 mg, 0.25 to 15 mg, 0.25 to 12 mg, 0.25 to 10 mg, 0.25 to 8 mg, 0.25 mg to 7 mg, 0.25 mg to 5 mg, 0.5 mg to 2.5 mg, 1 mg to 20 mg, 1 mg to 15 mg, 1 mg to 12 mg, 1 mg to 10 mg, 1 mg to 8 mg, 1 mg to 7 mg, 1 mg to 5 mg, or 1 mg to 2.5 mg. The unit dose can be administered 1, 2, 3, 4 or more times daily, or once every 2, 3, 4, 5, 6 or 7 days, or once weekly, once every two weeks, once every three weeks or once monthly.

In certain embodiments, when the triazolone compounds described herein are administered in combination with a BRAF inhibitor, the therapies are administered less than 5 minutes apart, less than 30 minutes apart, 1 hour apart, at about 1 hour apart, at about 1 to about 2 hours apart, at about 2 hours to about 3 hours apart, at about 3 hours to about 4 hours apart, at about 4 hours to about 5 hours apart, at about 5 hours to about 6 hours apart, at about 6 hours to about 7 hours apart, at about 7 hours to about 8 hours apart, at about 8 hours to about 9 hours apart, at about 9 hours to about 10 hours apart, at about 10 hours to about 11 hours apart, at about 11 hours to about 12 hours apart, at about 12 hours to 18 hours apart, 18 hours to 24 hours apart, 24 hours to 36 hours apart, 36 hours to 48 hours apart, 48 hours to 52 hours apart, 52 hours to 60 hours apart, 60 hours to 72 hours apart, 72 hours to 84 hours apart, 84 hours to 96 hours apart, or 96 hours to 120 hours part. In an embodiment, two or more therapies are administered within the same patient visit.

In certain embodiments, one or more compounds described herein and one or more other the therapies (e.g., therapeutic agents) are cyclically administered. Cycling therapy involves the administration of a first therapy (e.g., a first prophylactic or therapeutic agents) for a period of time, followed by the administration of a second therapy (e.g., a second prophylactic or therapeutic agents) for a period of time, followed by the administration of a third therapy (e.g., a third prophylactic or therapeutic agents) for a period of time and so forth, and repeating this sequential administration, i.e., the cycle in order to reduce the development of resistance to one of the agents, to avoid or reduce the side effects of one of the agents, and/or to improve the efficacy of the treatment.

In certain embodiments, administration of the same compound described herein may be repeated and the administrations may be separated by at least 1 day, 2 days, 3 days, 5 days, 10 days, 15 days, 30 days, 45 days, 2 months, 75 days, 3 months, or 6 months. In other embodiments, administration of the same prophylactic or therapeutic agent may be repeated and the administration may be separated by at least at least 1 day, 2 days, 3 days, 5 days, 10 days, 15 days, 30 days, 45 days, 2 months, 75 days, 3 months, or 6 months.

In a specific embodiment, a method of preventing, treating, managing, or ameliorating a proliferative disorders, such as cancer, or one or more symptoms thereof, the methods comprising administering to a subject in need thereof a dose of at least 150 μg/kg, preferably at least 250 μg/kg, at least 500 μg/kg, at least 1 mg/kg, at least 5 mg/kg, at least 10 mg/kg, at least 25 mg/kg, at least 50 mg/kg, at least 75 mg/kg, at least 100 mg/kg, at least 125 mg/kg, at least 150 mg/kg, or at least 200 mg/kg or more of one or more compounds described herein once every day, preferably, once every 2 days, once every 3 days, once every 4 days, once every 5 days, once every 6 days, once every 7 days, once every 8 days, once every 10 days, once every two weeks, once every three weeks, or once a month. Alternatively, the dose can be divided into portions (typically equal portions) administered two, three, four or more times a day.

In an embodiment, the invention also provides a method of treating cancer with a BRAF mutation comprising administering to a subject in need thereof an effective amount of an Hsp90 inhibitor according to formulae (I) or (Ia), or a compound in Tables 1 or 2, or a tautomer, or a pharmaceutically acceptable salt thereof. In an embodiment, the Hsp90 inhibitor is 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof. In an embodiment, the Hsp90 inhibitor is 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof. In any one of the above embodiments, the cancer may be melanoma. In an embodiment, the cancer may be melanoma with a BRAF mutation. In an embodiment, the cancer may be melanoma with a BRAF^(V600E) mutation.

In an embodiment, the invention also provides the use of a compound of formulae (I) or (Ia), or a compound in Tables 1 or 2, or a pharmaceutically acceptable salt thereof for the manufacture of a medicament for the treatment of a subject with cancer. In an embodiment, the invention further provides the use of a compound of formulae (I) or (Ia), or a compound in Tables 1 or 2, or a pharmaceutically acceptable salt thereof for the manufacture of a medicament for the treatment of a subject with a cancer, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®). In an embodiment, the invention further provides the use of a compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, for the manufacture of a medicament for the treatment of a subject with a cancer, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®). In an embodiment, the invention further provides the use of a compound of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, for the manufacture of a medicament for the treatment of a subject with a cancer, in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®). In an embodiment, the invention further provides the use of the compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, for the manufacture of a medicament for the treatment of a subject with a cancer, in combination with PLX-4032. In an embodiment, the invention further provides the synergistic use of the compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, for the manufacture of a medicament for the treatment of a subject with a cancer, in combination with PLX-4032. In an embodiment, the invention further provides the use of the compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, for the manufacture of a medicament for the treatment of a subject with a cancer, in combination with sorafenib. In an embodiment, the invention further provides the synergistic use of the compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, for the manufacture of a medicament for the treatment of a subject with a cancer, in combination with sorafenib.

In an embodiment, the invention also provides a compound of formulae (I) or (Ia) or a pharmaceutically acceptable salt thereof for use in treating a subject with a cancer. In an embodiment, the invention also provides a compound of formulae (I) or (Ia) or a pharmaceutically acceptable salt thereof for use in treating a subject with cancer in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®). In an embodiment, the invention also provides a compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, for use in treating a subject with cancer in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®). In an embodiment, the invention also provides a compound of 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, for use in treating a subject with cancer in combination with a BRAF inhibitor such as PLX-4032 (vemurafenib), GDC-0879, PLX-4720, or sorafenib (Nexavar®). In an embodiment, the invention also provides a compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, for use in treating a subject with cancer in combination with PLX-4032. In an embodiment, the invention also provides a compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, for synergistic use in treating a subject with cancer in combination with PLX-4032. In an embodiment, the invention also provides a compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, for use in treating a subject with cancer in combination with sorafenib. In an embodiment, the invention also provides a compound of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer, or a pharmaceutically acceptable salt thereof, for synergistic use in treating a subject with cancer in combination with sorafenib.

EXAMPLES

Activating mutations in BRAF(V600E) occur in 60% of melanoma, 50% of papillary thyroid cancer and 10% of colon cancer. BRAF inhibitors have elicited significant clinical response in melanomas but acquired resistance frequently develops after initial responses. Therefore, consideration of new treatment strategies to block activity of mutant BRAF and deter therapeutic resistance is warranted. Heat shock protein 90 (Hsp90) is a molecular chaperone required for the stability of hundreds of client proteins, including the RAF family of kinases, and has emerged as a highly relevant anticancer target. Compound I is a second generation, small molecule Hsp90 inhibitor currently being evaluated in multiple clinical trials. To investigate the potential for Compound I in the treatment of melanoma, we evaluated its activity as monotherapy and in combination with targeted agents in BRAF(V600E)-addicted cancer models.

Combination of Ganetespib with BRAF Inhibitor PLX-4032 (Vemurafenib)

A. Materials and Methods

Cell Lines

Human melanoma cell lines carrying the V600E BRAF mutation (A375, SK-MEL-28, RPMI-7951) and human prostate cancer cells (LNCaP, 22Rv1) were purchased from the American Type Culture Collection (Manassas, Va.) and grown following ATCC recommendations, in the presence of fetal bovine serum (10%), 2 mM L-glutamine and antibiotics (100 IU/ml penicillin and 100 μg/ml streptomycin) purchased from Sigma Aldrich. Cells were maintained at 37° C., 5% CO₂ atmosphere.

Western Blotting

Cells, treated with compound for 24 hr, were lysed in RIPA buffer (CST, Danvers, Mass., USA) on ice and clarified by centrifugation. Equal amounts of proteins were resolved by SDS-PAGE and immunoblotted with indicated antibodies. The antigen-antibody complex was visualized and quantitated using an Odyssey system (LI-COR, Lincoln, Nebr., USA).

Cell Viability Assays

Cell viability was measured using the Cell Titer-Glo assay (Promega). In brief, cells were plated in 96-well plates in triplicate at optimal seeding density (determined empirically for each cell line) and incubated at 37° C., 5% CO₂ atmosphere for 24 hr prior to the addition of drug or vehicle (0.3% DMSO) to the culture medium. At the end of the assay, Cell Titer-Glow was added to the wells per manufactures recommendation, shaken for two minutes and incubated for 10 minutes at room temperature. Luminescence (0.1 sec) was measured with a Victor II microplate reader (Perkin Elmer) and the resulting data were used to calculate cell viability, normalized to vehicle control.

Mouse Studies

Six to seven week old, female CB17/Icr-Prkdc^(scid)/Crl (SCID) mice were obtained from Charles River Laboratories (Wilmington, Mass., USA). Animals were housed 4-5/cage in micro-isolators, with a 12 hr/12 hr light/dark cycle, acclimated for at least 1 week prior to use and fed normal laboratory chow ad libitum. Animals were between seven to eight weeks of age at implantation. To implant A375 or 22Rv1 tumor cells into SCID mice, cells were harvested by trypsinization, washed in PBS and resusupended at a concentration of 5×10(7) cells/mL in 50% non-supplemented medium and 50% Matrigel Basement Membrane Matrix (BD Biosciences; Bedford, Mass., USA). Using a 27 gauge needle and 1 cc syringe, 5×10(6) cells in 0.1 mL of a cell suspension were injected subcutaneously into the flanks of SCID mice.

Tumors were then permitted to develop in vivo until the majority reached 95-195 mm³ in tumor volume. Animals with oblong, very small or large tumors were discarded and only animals carrying tumors that displayed consistent growth rates were selected for studies. Tumor volumes (V) were calculated by caliper measurement of the width (W), length (L) and thickness (T) of tumors using the following formula: V=0.5236×(L×W×T). Animals were randomized into treatment groups so that the average tumor volumes of each group were similar at the start of dosing.

Ganetespib was prepared by dissolving the appropriate amounts of the compound in dimethyl sulfoxide (DMSO) by sonication in an ultrasonic water bath. Stock solutions were prepared weekly, stored at −20° C. and diluted fresh each day for dosing. A solution of 20% Cremophor RH40 (polyoxyl 40 hydrogenated castor oil; BASF Corp., Aktiengesellschaft, Ludwigshafen, Germany) in 5% dextrose in water (Abbott Laboratories, North Chicago, Ill., USA) was also prepared by first heating 100% Cremophor RH40 at 50-60° C. until liquefied and clear, diluting 1:5 with 100% D5W, reheating again until clear and then mixing well. This solution can be stored at room temperature for up to 3 months prior to use. To prepare DRD formulations for daily dosing, DMSO stock solutions were diluted 1:10 with 20% Cremophor RH40. The final DRD formulation for dosing contained 10% DMSO, 18% Cremophor RH40, 3.6% dextrose, 68.4% water and the appropriate amount of test article. Animals were intravenously (i.v.) injected with this formulation at 10 mL per kg body weight 1 day each week. AZD6244 was prepared fresh in 0.5% carboxylmethyl cellulose and given orally 5 days per week. BEZ235 was prepared fresh in 90% PEG300/10% NMP given orally 5 days per week.

B. Results

The frequency of BRAF mutations in melanoma is greater than 80%. Approximately 60% of those mutations are activating mutations in V600E [1]. Ganetespib showed considerable, low nanomolar activity in a large panel of human cancer cells harboring the V600E mutation in BRAF, with IC50 between 4 and 40 nM. (Table 1). At the protein level, ganetespib was fully capable of destabilizing mutant BRAF in A375 and SK-MEL-28 melanoma cells, resulting in the loss of MEK and ERK activity (FIG. 1). Importantly, ganetespib suppressed PI3K and mTOR-mediated phosphorylation of AKT and 4EBP1, and destabilized Cdc2, resulting in apoptosis as determined by PARP cleavage (FIG. 2).

Ganetespib treatment displayed greater potency in deactivating/dephosphorylating ERK than the BRAF inhibitor PLX-4032 (Selleck Chemicals, Houston, Tex.) or the MEK inhibitor AZD6244 (Selleck Chemicals, Houston, Tex.) (FIG. 3). Compound I was also able to destabilize the BRAF dimerization partner CRAF. Combining ganetespib with PLX-4032 resulted in greater activity than either agent alone both in vitro and in vivo (FIGS. 4 and 6).

The BRAF inhibitor PLX-4032 has displayed an 81% response rate in a phase I trials of patients with metastatic melanoma whose tumors were positive for the BRAF V600E mutation confirming that effective suppression of BRAF can be an effective strategy for treating such patients [2]. While the initial response rate to PLX-4032 is high, acquired drug resistance frequently develops after initial responses. One such mechanism behind this resistance is through the upregulation of MAP3K8, encoding the kinase COT [3]. Shown in FIG. 5, neither the MEK inhibitor AZD6244 nor the BRAF inhibitor PLX-4032 were capable of suppressing ERK phosphorylation in RPMI-7951 melanoma cells previously shown to overexpress COT [3]. In contrast, ganetespib effectively inhibited MEK and ERK activity, as well as AKT activity. As a result, ganetespib potently killed RPMI-7951 cells with an IC90 of 10 nM. As expected, neither AZD6244 nor PLX-4032 were capable of killing more than 40% of the cells at concentrations of 1 μM.

Taken together, ganetespib is highly effective in killing melanoma cells in at least two distinct ways. The first way is through destabilization of mutant BRAF. The second is through disruption of COT/ERK signaling in melanoma cells resistant to MEK and BRAF inhibitors.

TABLE 1 Compound 1 in a panel of BRAF mutant cancer cell lines Ganetespib BRAF Cell Line IC50 (nM) Histology Status ACN 4 neuroblastoma V600E RKO 4 carcinoma V600E IST-MEL1 4 malignant melanoma V600E LS-411N 5 carcinoma V600E COLO-829 5 malignant melanoma V600E HT-144 6 malignant melanoma V600E SK-HEP-1 9 carcinoma V600E A101D 9 malignant melanoma V600E SW982 10 synovial sarcoma V600E K5 11 carcinoma V600E SH-4 12 malignant melanoma V600E DBTRG-05MG 14 glioma V600E SK-MEL-5 18 malignant melanoma V600E A375 20 malignant melanoma V600E HTC-C3 21 carcinoma V600E SW872 22 liposarcoma V600E UACC-257 24 malignant melanoma V600E RVH-421 26 malignant melanoma V600E MZ7-mel 26 malignant melanoma V600E MMAC-SF 31 malignant melanoma V600E 1. Nazarian, R., et al., Melanomas acquire resistance to B-RAF(V600E) inhibition by RTK or N-RAS upregulation. Nature. 468(7326): p. 973-7. 2. Flaherty, K. T., et al., Inhibition of Mutated, Activated BRAF in Metastatic Melanoma. New England Journal of Medicine. 363(9): p. 809-819. 3. Johannessen, C. M., et al., COT drives resistance to RAF inhibition through MAP kinase pathway reactivation. Nature. 468(7326): p. 968-72.

In conclusion, these data support the use of ganetespib in combination with a BRAF inhibitor such as PLX-4032 or sorafenib in treating cancer such as melanoma or non-small cell lung cancer. The data also support single agent use of ganetespib in treating cancer with a BRAF mutation.

All publications, patent applications, patents, and other documents cited herein are incorporated by reference in their entirety. In case of conflict, the present specification, including definitions, will control. In addition, the materials, methods, and examples throughout the specification are illustrative only and not intended to be limiting in any way. 

What is claimed is:
 1. A pharmaceutical composition comprising a BRAF inhibitor and an Hsp90 inhibitor according to the following formula:

or a tautomer, or a pharmaceutically acceptable salt thereof, wherein: Z is OH, SH, or NH₂; X is CR₄ or N; R₁ is —H, —OH, —SH, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, an optionally substituted heteraralkyl, halo, cyano, nitro, guanidino, a haloalkyl, a heteroalkyl, an alkoxy or cycloalkoxy, a haloalkoxy, —NR₁₀R₁₁, —OR₇, —C(O)R₇, —C(O)OR₇, —C(S)R₇, —C(O)SR₇, —C(S)SR₇, —C(S)OR₇, —C(S)NR₁₀R₁₁, —C(NR₈)OR₇, —C(NR₈)R₇, —C(NR₈)NR₁₀R₁₁, —C(NR₈)SR₇, —OC(O)R₇, —OC(O)OR₇, —OC(S)OR₇, —OC(NR₈)OR₇, —SC(O)R₇, —SC(O)OR₇, —SC(NR₈)OR₇, —OC(S)R₇, —SC(S)R₇, —SC(S)OR₇, —OC(O)NR₁₀R₁₁, —OC(S)NR₁₀R₁₁, —OC(NR₈)NR₁₀R₁₁, —SC(O)NR₁₀R₁₁, —SC(NR₈)NR₁₀R₁₁, —SC(S)NR₁₀R₁₁, —OC(NR₈)R₇, —SC(NR₈)R₇, —C(O)NR₁₀R₁₁, —NR₈C(O)R₇, —NR₇C(S)R₇, —NR₇C(S)OR₇, —NR₇C(NR₈)R₇, —NR₇C(O)OR₇, —NR₇C(NR₈)OR₇, —NR₇C(O)NR₁₀R₁₁, —NR₇C(S)NR₁₀R₁₁, —NR₇C(NR₈)NR₁₀R₁₁, —SR₇, —S(O)_(p)R₇, —OS(O)_(p)R₇, —OS(O)_(p)OR₇, —OS(O)_(p)NR₁₀R₁₁, —S(O)_(p)OR₇, —NR₈S(O)_(p)R₇, —NR₇S(O)_(p)NR₁₀R₁₁, —NR₇S(O)_(p)OR₇, —S(O)_(p)NR₁₀R₁₁, —SS(O)_(p)R₇, —SS(O)_(p)OR₇, —SS(O)_(p)NR₁₀R₁₁, —OP(O)(OR₇)₂, or —SP(O)(OR₇)₂; R₂ is —H, —OH, —SH, —NR₇H, —OR₁₅, —SR₁₅, —NHR₁₅, —O(CH₂)_(m)OH, —O(CH₂)_(m)SH, —O(CH₂)_(m)NR₇H, —S(CH₂)_(m)OH, —S(CH₂)_(m)SH, —S(CH₂)_(m)NR₇H, —OC(O)NR₁₀R₁₁, —SC(O)NR₁₀R₁₁, —NR₇C(O)NR₁₀R₁₁, —OC(O)R₇, —SC(O)R₇, —NR₇C(O)R₇, —OC(O)OR₇, —SC(O)OR₇, —NR₇C(O)OR₇, —OCH₂C(O)R₇, —SCH₂C(O)R₇, —NR₇CH₂C(O)R₇, —OCH₂C(O)OR₇, —SCH₂C(O)OR₇, —NR₇CH₂C(O)OR₇, —OCH₂C(O)NR₁₀R₁₁, —SCH₂C(O)NR₁₀R₁₁, —NR₇CH₂C(O)NR₁₀R₁₁, —OS(O)_(p)R₇, —SS(O)_(p)R₇, —NR₇S(O)_(p)R₇, —OS(O)_(p)NR₁₀R₁₁, —SS(O)_(p)NR₁₀R₁₁, —NR₇S(O)_(p)NR₁₀R₁₁, —OS(O)_(p)OR₇, —SS(O)_(p)OR₇, —NR₇S(O)_(p)OR₇, —OC(S)R₇, —SC(S)R₇, —NR₇C(S)R₇, —OC(S)OR₇, —SC(S)OR₇, —NR₇C(S)OR₇, —OC(S)NR₁₀R₁₁, —SC(S)NR₁₀R₁₁, —NR₇C(S)NR₁₀R₁₁, —OC(NR₈)R₇, —SC(NR₈)R₇, —NR₇C(NR₈)R₇, —OC(NR₈)OR₇, —SC(NR₈)OR₇, —NR₇C(NR₈)OR₇, —OC(NR₈)NR₁₀R₁₁, —SC(NR₈)NR₁₀R₁₁, or —NR₇C(NR₈)NR₁₀R₁₁; R₃ is —H, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, an optionally substituted heteraralkyl, hydroxyalkyl, alkoxyalkyl, a haloalkyl, a heteroalkyl, —C(O)R₇, —(CH₂)_(m)C(O)OR₇, —C(O)OR₇, —OC(O)R₇, —C(O)NR₁₀R₁₁, —S(O)_(p)R₇, —S(O)_(p)OR₇, or —S(O)_(p)NR₁₀R₁₁; R₄ is —H, —OH, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, an optionally substituted heteraralkyl, hydroxyalkyl, alkoxyalkyl, halo, cyano, nitro, guanidino, a haloalkyl, a heteroalkyl, —C(O)R₇, —C(O)OR₇, —OC(O)R₇, —C(O)NR₁₀R₁₁, —NR₈C(O)R₇, —SR₇, —S(O)_(p)R₇, —OS(O)_(p)R₇, —S(O)_(p)OR₇, —NR₈S(O)_(p)R₇, —S(O)_(p)NR₁₀R₁₁, or R₃ and R₄ taken together with the carbon atoms to which they are attached form an optionally substituted cycloalkenyl, an optionally substituted aryl, an optionally substituted heterocyclyl, or an optionally substituted heteroaryl; R₇ and R₈, for each occurrence, are, independently, —H, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, or an optionally substituted heteraralkyl; R₁₀ and R₁₁, for each occurrence, are independently —H, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, or an optionally substituted heteraralkyl; or R₁₀ and R₁₁, taken together with the nitrogen to which they are attached, form an optionally substituted heterocyclyl or an optionally substituted heteroaryl; R₁₅, for each occurrence, is independently, a lower alkyl; p, for each occurrence, is independently 1 or 2; and m, for each occurrence, is independently 1, 2, 3, or 4, and wherein the BRAF inhibitor is selected from the group consisting of vemurafenib and PLX—4720.
 2. The pharmaceutical composition of claim 1, wherein the Hsp90 inhibitor is 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole or a tautomer or a pharmaceutically acceptable salt thereof.
 3. The pharmaceutical composition of claim 1, wherein the Hsp90 inhibitor is 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof.
 4. The pharmaceutical composition of claim 1, wherein the BRAF inhibitor is vemurafenib.
 5. The pharmaceutical composition of claim 1, wherein the Hsp90 inhibitor is 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer or a pharmaceutically acceptable salt thereof, and the BRAF inhibitor is vemurafenib.
 6. The pharmaceutical composition of claim 1, wherein the Hsp90 inhibitor is 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, and the BRAF inhibitor is vemurafenib.
 7. A method of treating cancer in a subject having cancer, comprising administering to the subject an effective amount of a BRAF inhibitor and an effective amount of an Hsp90 inhibitor, according to the following formula:

or a tautomer, or a pharmaceutically acceptable salt thereof;, wherein: Z is OH, SH, or NH₂; X is CR₄ or N: R₁ is —H, —OH, —SH, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, an optionally substituted heteroaralkyl, halo, cyano, nitro, guanidino, a haloalkyl, a heteroalkyl, an alkoxy or cycloalkoxy, a haloalkoxy, —NR₁₀R₁₁, —OR₇, —C(O)R₇, —C(O)OR₇, —C(S)R₇, —C(O)SR₇, —C(S)SR₇, —C(S)OR₇, —C(S)NR₁₀R₁₁, —C(NR₈)OR₇, —C(NR₈)R₇, —C(NR₈)NR₁₀R₁₁, —C(NR₈)SR₇, —OC(O)R₇, —OC(O)OR₇, —OC(S)OR₇, —OC(NR₈)OR₇, —SC(O)R₇, —SC(O)OR₇, —SC(NR₈)OR₇, —OC(S)R₇, —SC(S)R₇, —SC(S)OR₇, —OC(O)NR₁₀R₁₁, —OC(S)NR₁₀R₁₁, —OC(NR₈)NR₁₀R₁₁, —SC(O)NR₁₀R₁₁, —SC(NR₈)NR₁₀R₁₁, —SC(S)NR₁₀R₁₁, —OC(NR₈)R₇, —SC(NR₈)R₇, —C(O)NR₁₀R₁₁, —NR₈C(O)R₇, —NR₇C(S)R₇, —NR₇C(S)OR₇, —NR₇C(NR₈)R₇, —NR₇C(O)OR₇, —NR₇C(NR₈)OR₇, —NR₇C(O)NR₁₀R₁₁, —NR₇C(S)NR₁₀R₁₁, —NR₇C(NR₈)NR₁₀R₁₁, —SR₇, —S(O)_(p)R₇, —OS(O)_(p)OR₇, —OS(O)_(p)NR₁₀R₁₁, —S(O)_(p)OR₇, —NR₈S(O)_(p)R₇, —NR₇S(O)_(p)NR₁₀R₁₁, —NR₇S(O)_(p)OR₇, —S(O)_(p)NR₁₀R₁₁, —SS(O)_(p)R₇, —SS(O)_(p)OR₇, —SS(O)_(p)NR₁₀R₁₁, —OP(O)(OR₇)₂, or —SP(O)(OR₇)₂; R₂ is —H, —OH, —SH, —NR₇H, —OR₁₅, —SR₁₅, —NHR₁₅, —O(CH₂)_(m)OH, —O(CH₂)_(m)SH, —O(CH₂)_(m)NR₇H, —S(CH₂)_(m)OH, —S(CH₂)_(m)SH, —S(CH₂)_(m)NR₇H, —OC(O)NR₁₀R₁₁, —SC(O)NR₁₀R₁₁, —NR₇C(O)NR₁₀R₁₁, —OC(O)R₇, —SC(O)R₇, —NR₇C(O)R₇, —OC(O)OR₇, —SC(O)OR₇, —NR₇C(O)OR₇, —OCH₂C(O)R₇, —SCH₂C(O)R₇, —NR₇CH₂C(O)R₇, —OCH₂C(O)OR₇, —SCH₂C(O)OR₇, —NR₇CH₂C(O)OR₇, —OCH₂C(O)NR₁₀R₁₁, —SCH₂C(O)NR₁₀R₁₁, —NR₇CH₂C(O)NR₁₀R₁₁, —OS(O)_(p)R₇, —SS(O)_(p)R₇, —NR₇S(O)_(p)R₇, —OS(O)_(p)NR₁₀R₁₁, —SS(O)_(p)NR₁₀R₁₁, —NR₇S(O)_(p)NR₁₀R₁₁, —OS(O)_(p)OR₇, —SS(O)_(p)OR₇, —NR₇S(O)_(p)OR₇, —OC(S)R₇, —SC(S)R₇, —NR₇C(S)R₇, —OC(S)OR₇, —SC(S)OR₇, —NR₇C(S)OR₇, —OC(S)NR₁₀R₁₁, —SC(S)NR₁₀R₁₁, —NR₇C(S)NR₁₀R₁₁, —OC(NR₈)R₇, —SC(NR₈)R₇, —NR₇C(NR₈)R₇, —OC(NR₈)OR₇, —SC(NR₈)OR₇, —NR₇C(NR₈)OR₇, —OC(NR₈)NR₁₀R₁₁, —SC(NR₈)NR₁₀R₁₁, or —NR₇C(NR₈)NR₁₀R₁₁; R₃ is —H, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, an optionally substituted heteroaralkyl, hydroxyalkyl, alkoxyalkyl, a haloalkyl, a heteroalkyl, —C(O)R₇, —(CH₂)_(m)C(O)OR₇, —C(O)OR₇, —OC(O)R₇, —C(O)NR₁₀R₁₁, —S(O)_(p)R₇, —S(O)_(p)OR₇, or —S(O)_(p)NR₁₀R₁₁; R₄ is —H, —OH, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, an optionally substituted heteroaralkyl, hydroxyalkyl, alkoxyalkyl, halo, cyano, nitro, guanidino, a haloalkyl, a heteroalkyl, —C(O)R₇, —C(O)OR₇, —OC(O)R₇, —C(O)NR₁₀R₁₁, —NR₈C(O)R₇, —SR₇, —S(O)_(p)R₇, —OS(O)_(p)R₇, —S(O)_(p)OR₇, —NR₈S(O)_(p)R₇, —S(O)_(p)NR₁₀R₁₁, or R₃ and R₄ taken together with the carbon atoms to which they are attached form an optionally substituted cycloalkenyl, an optionally substituted aryl, an optionally substituted heterocyclyl, or an optionally substituted heteroaryl; R₇ and R₈, for each occurance, are independently, —H, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, or an optionally substituted heteroaralkyl; R₁₀ and R₁₁, for each occurrence, are independently —H, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, or an optionally substituted heteroaralkyl; or R₁₀ and R₁₁, taken together with the nitrogen to which they are attached, form an optionally substituted heterocyclyl or an optionally substituted heteroaryl; R₁₅, for each occurrence, is independently, a lower alkyl; p, for each occurrence, is independently 1 or 2; and m, for each occurrence, is independently 1, 2, 3, or 4, and wherein the BRAF inhibitor is selected from the group consisting of vemurafenib and PLX-4720.
 8. The method of claim 7, wherein the cancer is breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, ocular melanoma, prostate cancer, gastrointestinal stromal tumors (GIST), advanced esophagogastric cancer, melanoma, hepatocellular cancer, solid tumor, liver cancer, head and neck cancer, small cell lung cancer, non-small cell lung cancer, bladder cancer, testicular tumor, ovarian cancer, lymphoma, leukemia, multiple myeloma, anaplastic thyroid carcinoma, papillary thyroid carcinoma, Barrett's esophageal carcinoma, or colon cancer.
 9. The method of claim 8, wherein the cancer is breast cancer, gastric cancer, non-small cell lung cancer, ovarian cancer, melanoma, pancreatic cancer, or colorectal cancer.
 10. The method of claim 9, wherein the cancer is melanoma.
 11. The method of claim 10, wherein the melanoma is unresectable or metastatic.
 12. The method of claim 10, wherein the melanoma has a BRAF^(V600E) mutation.
 13. The method of claim 9, wherein the cancer is non-small cell lung cancer.
 14. The method of claim 9, wherein the cancer is breast cancer.
 15. The method of claim 7, comprising administering an effective amount of 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer or a pharmaceutically acceptable salt thereof, and vemurafenib, wherein the cancer is breast cancer, gastric cancer, non-small cell lung cancer, ovarian cancer, melanoma, pancreatic cancer, or colorectal cancer.
 16. A method of inhibiting the growth of a cancer or tumor cell in a subject, the method comprising the steps of: (a) contacting the cell with an effective amount of an Hsp90 inhibitor of, according to the following formula:

or a tautomer, or a pharmaceutically acceptable salt thereof; wherein: Z is OH, SH, or NH₂; X is CR₄ or N; R₁ is —H, —OH, —SH, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, an optionally substituted heteroaralkyl, halo, cyano, nitro, guanidino, a haloalkyl, a heteroalkyl, an alkoxy or cycloalkoxy, a haloalkoxy, —NR₁₀R₁₁, —OR₇, —C(O)R₇, —C(O)OR₇, —C(S)R₇, —C(O)SR₇, —C(S)SR₇, —C(S)OR₇, —C(S)NR₁₀R₁₁, —C(NR₈)OR₇, —C(NR₈)R₇, —C(NR₈)NR₁₀R₁₁, —C(NR₈)SR₇, —OC(O)R₇, —OC(O)OR₇, —OC(S)OR₇, —OC(NR₈)OR₇, —SC(O)R₇, —SC(O)OR₇, —SC(NR₈)OR₇, —OC(S)R₇, —SC(S)R₇, —SC(S)OR₇, —OC(O)NR₁₀R₁₁, —OC(S)NR₁₀R₁₁, —OC(NR₈)NR₁₀R₁₁, —SC(O)NR₁₀R₁₁, —SC(NR₈)NR₁₀R₁₁, —SC(S)NR₁₀R₁₁, —OC(NR₈)R₇, —SC(NR₈)R₇, —C(O)NR₁₀R₁₁, —NR₈C(O)R₇, —NR₇C(S)R₇, —NR₇C(S)OR₇, —NR₇C(NR₈)R₇, —NR₇C(O)OR₇, —NR₇C(NR₈)OR₇, —NR₇C(O)NR₁₀R₁₁, —NR₇C(S)NR₁₀R₁₁, —NR₇C(NR₈)NR₁₀R₁₁, —SR₇, —S(O)_(p)R₇, —OS(O)_(p)R₇, —OS(O)_(p)OR₇, —OS(O)_(p)NR₁₀R₁₁, —S(O)_(p)OR₇, —NR₈S(O)_(p)R₇, —NR₇S(O)_(p)NR₁₀R₁₁, —NR₇S(O)_(p)OR₇, —S(O)_(p)NR₁₀R₁₁, —SS(O)_(p)R₇, —SS(O)_(p)OR₇, —SS(O)_(p)NR₁₀R₁₁, —OP(O)(OR₇)₂, or —SP(O)(OR₇)₂; R₂ is —H, —OH, —SH, —NR₇H, —OR₁₅, —SR₁₅, —NHR₁₅, —O(CH₂)_(m)OH, —O(CH₂)_(m)SH, —O(CH₂)_(m)NR₇H, —S(CH₂)_(m)OH, —S(CH₂)_(m)SH, —S(CH₂)_(m)NR₇H, —OC(O)NR₁₀R₁₁, —SC(O)NR₁₀R₁₁, —NR₇C(O)NR₁₀R₁₁, —OC(O)R₇, —SC(O)R₇, —NR₇C(O)R₇, —OC(O)OR₇, —SC(O)OR₇, —NR₇C(O)OR₇, —OCH₂C(O)R₇, —SCH₂C(O)R₇, —NR₇CH₂C(O)R₇, —OCH₂C(O)OR₇, —SCH₂C(O)OR₇, —NR₇CH₂C(O)OR₇, —OCH₂C(O)NR₁₀R₁₁, —SCH₂C(O)NR₁₀R₁₁, —NR₇CH₂C(O)NR₁₀R₁₁, —OS(O)_(p)R₇, —SS(O)_(p)R₇, —NR₇S(O)_(p)R₇, —OS(O)_(p)NR₁₀R₁₁, —SS(O)_(p)NR₁₀R₁₁, —NR₇S(O)_(p)NR₁₀R₁₁, —OS(O)_(p)OR₇, —SS(O)_(p)OR₇, —NR₇S(O)_(p)OR₇, —OC(S)R₇, —SC(S)R₇, —NR₇C(S)R₇, —OC(S)OR₇, —SC(S)OR₇, —NR₇C(S)OR₇, —OC(S)NR₁₀R₁₁, —SC(S)NR₁₀R₁₁, —NR₇C(S)NR₁₀R₁₁, —OC(NR₈)R₇, —SC(NR₈)R₇, —NR₇C(NR₈)R₇, —OC(NR₈)OR₇, —SC(NR₈)OR₇, —NR₇C(NR₈)OR₇, —OC(NR₈)NR₁₀R₁₁, —SC(NR₈)NR₁₀R₁₁, or —NR₇C(NR₈)NR₁₀R₁₁; R₃ is —H, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, an optionally substituted heteroaralkyl, hydroxyalkyl, alkoxyalkyl, a haloalkyl, a heteroalkyl, —C(O)R₇, —(CH₂)_(m)C(O)OR₇, —C(O)OR₇, —OC(O)R₇, —C(O)NR₁₀R₁₁, —S(O)_(p)R₇, —S(O)_(p)OR₇, or —S(O)_(p)NR₁₀R₁₁; R₄ is —H, —OH, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, an optionally substituted heteroaralkyl, hydroxyalkyl, alkoxyalkyl, halo, cyano, nitro, guanidino, a haloalkyl, a heteroalkyl, —C(O)R₇, —C(O)OR₇, —OC(O)R_(7,) —C(O)NR₁₀R₁₁ , —NR₈C(O)R₇, —SR₇, —S(O)_(p)R₇, —OS(O)_(p)R₇, —S(O)_(p)OR₇, —NR₈S(O)_(p)R₇, —S(O)_(p)NR₁₀R₁₁ , or R₃ and R₄ taken together with the carbon atoms to which they are attached form an optionally substituted cycloalkenyl, an optionally substituted aryl, an optionally substituted heterocyclyl, or an optionally substituted heteroaryl; R₇ and R₈, for each occurrence, are independently, —H, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, or an optionally substituted heteroaralkyl; R₁₀ and R₁₁, for each occurrence, are independently —H, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heterocyclyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl, or an optionally substituted heteroaralkyl; or R₁₀ and R₁₁, taken together with the nitrogen to which they are attached, form an optionally substituted heterocyclyl or an optionally substituted heteroaryl; R₁₅, for each occurrence, is independently, a lower alkyl; p, for each occurrence, is independently 1 or 2; and m, for each occurrence, is independently 1, 2, 3, or 4, and wherein the BRAF inhibitor is selected from the group consisting of vemurafenib and PLX-4720, and (b) exposing the cell to an effective amount of a BRAF inhibitor, wherein the BRAF inhibitor is selected from the group consisting of vemurafenib, and PLX-4720.
 17. The method of claim 16, wherein the compound is 3-(2,4-dihydroxy-5-isopropyl-phenyl)-4-(1-methyl-indol-5-yl)-5-hydroxy-[1,2,4]triazole, or a tautomer or a pharmaceutically acceptable salt thereof and the BRAF inhibitor is vemurafenib.
 18. The method of claim 16, wherein the compound is 5-hydroxy-4-(5-hydroxy-4-(1-methyl-1H-indol-5-yl)-4H-1,2,4-triazol-3-yl)-2-isopropylphenyl dihydrogen phosphate, or a tautomer, or a pharmaceutically acceptable salt thereof, and the BRAF inhibitor is vemurafenib. 